Use of sound to elicit a response in the nervous system.
The audibility limit of discriminating sound intensity and pitch.
The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.
Use of electric potential or currents to elicit biological responses.
The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.
Electronic hearing devices typically used for patients with normal outer and middle ear function, but defective inner ear function. In the COCHLEA, the hair cells (HAIR CELLS, VESTIBULAR) may be absent or damaged but there are residual nerve fibers. The device electrically stimulates the COCHLEAR NERVE to create sound sensation.
Wearable sound-amplifying devices that are intended to compensate for impaired hearing. These generic devices include air-conduction hearing aids and bone-conduction hearing aids. (UMDNS, 1999)
NEURAL PATHWAYS and connections within the CENTRAL NERVOUS SYSTEM, beginning at the hair cells of the ORGAN OF CORTI, continuing along the eighth cranial nerve, and terminating at the AUDITORY CORTEX.
Self-generated faint acoustic signals from the inner ear (COCHLEA) without external stimulation. These faint signals can be recorded in the EAR CANAL and are indications of active OUTER AUDITORY HAIR CELLS. Spontaneous otoacoustic emissions are found in all classes of land vertebrates.
The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.
Measurement of the ability to hear speech under various conditions of intensity and noise interference using sound-field as well as earphones and bone oscillators.
Electrical waves in the CEREBRAL CORTEX generated by BRAIN STEM structures in response to auditory click stimuli. These are found to be abnormal in many patients with CEREBELLOPONTINE ANGLE lesions, MULTIPLE SCLEROSIS, or other DEMYELINATING DISEASES.
The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.
A general term for the complete loss of the ability to hear from both ears.
Surgical insertion of an electronic hearing device (COCHLEAR IMPLANTS) with electrodes to the COCHLEAR NERVE in the inner ear to create sound sensation in patients with residual nerve fibers.
The cochlear part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). The cochlear nerve fibers originate from neurons of the SPIRAL GANGLION and project peripherally to cochlear hair cells and centrally to the cochlear nuclei (COCHLEAR NUCLEUS) of the BRAIN STEM. They mediate the sense of hearing.
Any sound which is unwanted or interferes with HEARING other sounds.
An oval semitransparent membrane separating the external EAR CANAL from the tympanic cavity (EAR, MIDDLE). It contains three layers: the skin of the external ear canal; the core of radially and circularly arranged collagen fibers; and the MUCOSA of the middle ear.
A general term for the complete or partial loss of the ability to hear from one or both ears.
The science pertaining to the interrelationship of psychologic phenomena and the individual's response to the physical properties of sound.
The graphic registration of the frequency and intensity of sounds, such as speech, infant crying, and animal vocalizations.
Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.
The process whereby an utterance is decoded into a representation in terms of linguistic units (sequences of phonetic segments which combine to form lexical and grammatical morphemes).
Ability to determine the specific location of a sound source.
The posterior pair of the quadrigeminal bodies which contain centers for auditory function.
A part of the MEDULLA OBLONGATA situated in the olivary body. It is involved with motor control and is a major source of sensory input to the CEREBELLUM.
The brain stem nucleus that receives the central input from the cochlear nerve. The cochlear nucleus is located lateral and dorsolateral to the inferior cerebellar peduncles and is functionally divided into dorsal and ventral parts. It is tonotopically organized, performs the first stage of central auditory processing, and projects (directly or indirectly) to higher auditory areas including the superior olivary nuclei, the medial geniculi, the inferior colliculi, and the auditory cortex.
The testing of the acuity of the sense of hearing to determine the thresholds of the lowest intensity levels at which an individual can hear a set of tones. The frequencies between 125 and 8000 Hz are used to test air conduction thresholds and the frequencies between 250 and 4000 Hz are used to test bone conduction thresholds.
Sensory cells of organ of Corti. In mammals, they are usually arranged in three or four rows, and away from the core of spongy bone (the modiolus), lateral to the INNER AUDITORY HAIR CELLS and other supporting structures. Their cell bodies and STEREOCILIA increase in length from the cochlear base toward the apex and laterally across the rows, allowing differential responses to various frequencies of sound.
Measurement of hearing based on the use of pure tones of various frequencies and intensities as auditory stimuli.
The process whereby auditory stimuli are selected, organized, and interpreted by the organism.
Sensory cells in the organ of Corti, characterized by their apical stereocilia (hair-like projections). The inner and outer hair cells, as defined by their proximity to the core of spongy bone (the modiolus), change morphologically along the COCHLEA. Towards the cochlear apex, the length of hair cell bodies and their apical STEREOCILIA increase, allowing differential responses to various frequencies of sound.
A subfamily of the Muridae consisting of several genera including Gerbillus, Rhombomys, Tatera, Meriones, and Psammomys.
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
Elements of limited time intervals, contributing to particular results or situations.
Application of electric current in treatment without the generation of perceptible heat. It includes electric stimulation of nerves or muscles, passage of current into the body, or use of interrupted current of low intensity to raise the threshold of the skin to pain.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
The increase in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Therapy for MOVEMENT DISORDERS, especially PARKINSON DISEASE, that applies electricity via stereotactic implantation of ELECTRODES in specific areas of the BRAIN such as the THALAMUS. The electrodes are attached to a neurostimulator placed subcutaneously.
Act of eliciting a response from a person or organism through physical contact.
A technique that involves the use of electrical coils on the head to generate a brief magnetic field which reaches the CEREBRAL CORTEX. It is coupled with ELECTROMYOGRAPHY response detection to assess cortical excitability by the threshold required to induce MOTOR EVOKED POTENTIALS. This method is also used for BRAIN MAPPING, to study NEUROPHYSIOLOGY, and as a substitute for ELECTROCONVULSIVE THERAPY for treating DEPRESSION. Induction of SEIZURES limits its clinical usage.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The use of specifically placed small electrodes to deliver electrical impulses across the SKIN to relieve PAIN. It is used less frequently to produce ANESTHESIA.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.
A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.
Established cell cultures that have the potential to propagate indefinitely.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
The 10th cranial nerve. The vagus is a mixed nerve which contains somatic afferents (from skin in back of the ear and the external auditory meatus), visceral afferents (from the pharynx, larynx, thorax, and abdomen), parasympathetic efferents (to the thorax and abdomen), and efferents to striated muscle (of the larynx and pharynx).
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The rate dynamics in chemical or physical systems.
Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.
Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.
The electrical response evoked in a muscle or motor nerve by electrical or magnetic stimulation. Common methods of stimulation are by transcranial electrical and TRANSCRANIAL MAGNETIC STIMULATION. It is often used for monitoring during neurosurgery.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Isopropyl analog of EPINEPHRINE; beta-sympathomimetic that acts on the heart, bronchi, skeletal muscle, alimentary tract, etc. It is used mainly as bronchodilator and heart stimulant.
An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.
Recording of the changes in electric potential of muscle by means of surface or needle electrodes.
Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex.
Lens-shaped structure on the inner aspect of the INTERNAL CAPSULE. The SUBTHALAMIC NUCLEUS and pathways traversing this region are concerned with the integration of somatic motor function.
Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
The thoracolumbar division of the autonomic nervous system. Sympathetic preganglionic fibers originate in neurons of the intermediolateral column of the spinal cord and project to the paravertebral and prevertebral ganglia, which in turn project to target organs. The sympathetic nervous system mediates the body's response to stressful situations, i.e., the fight or flight reactions. It often acts reciprocally to the parasympathetic system.
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
The function of opposing or restraining the excitation of neurons or their target excitable cells.
Stimulation of the brain, which is self-administered. The stimulation may result in negative or positive reinforcement.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.
A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.
Neurons which activate MUSCLE CELLS.
An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters.
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
Drugs that selectively bind to and activate beta-adrenergic receptors.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Application of electric current to the spine for treatment of a variety of conditions involving innervation from the spinal cord.
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
The time from the onset of a stimulus until a response is observed.
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.
A slowly hydrolyzed CHOLINERGIC AGONIST that acts at both MUSCARINIC RECEPTORS and NICOTINIC RECEPTORS.
A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.
The craniosacral division of the autonomic nervous system. The cell bodies of the parasympathetic preganglionic fibers are in brain stem nuclei and in the sacral spinal cord. They synapse in cranial autonomic ganglia or in terminal ganglia near target organs. The parasympathetic nervous system generally acts to conserve resources and restore homeostasis, often with effects reciprocal to the sympathetic nervous system.
A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.
One of two major pharmacologically defined classes of adrenergic receptors. The beta adrenergic receptors play an important role in regulating CARDIAC MUSCLE contraction, SMOOTH MUSCLE relaxation, and GLYCOGENOLYSIS.
Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)
Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Neural tracts connecting one part of the nervous system with another.
The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.
Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)
Contractile tissue that produces movement in animals.
Area of the parietal lobe concerned with receiving sensations such as movement, pain, pressure, position, temperature, touch, and vibration. It lies posterior to the central sulcus.
The major nerves supplying sympathetic innervation to the abdomen. The greater, lesser, and lowest (or smallest) splanchnic nerves are formed by preganglionic fibers from the spinal cord which pass through the paravertebral ganglia and then to the celiac ganglia and plexuses. The lumbar splanchnic nerves carry fibers which pass through the lumbar paravertebral ganglia to the mesenteric and hypogastric ganglia.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Proteins prepared by recombinant DNA technology.
A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.
Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)
A widely used non-cardioselective beta-adrenergic antagonist. Propranolol has been used for MYOCARDIAL INFARCTION; ARRHYTHMIA; ANGINA PECTORIS; HYPERTENSION; HYPERTHYROIDISM; MIGRAINE; PHEOCHROMOCYTOMA; and ANXIETY but adverse effects instigate replacement by newer drugs.
Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.
Neurons which send impulses peripherally to activate muscles or secretory cells.
A condition characterized by abnormal posturing of the limbs that is associated with injury to the brainstem. This may occur as a clinical manifestation or induced experimentally in animals. The extensor reflexes are exaggerated leading to rigid extension of the limbs accompanied by hyperreflexia and opisthotonus. This condition is usually caused by lesions which occur in the region of the brainstem that lies between the red nuclei and the vestibular nuclei. In contrast, decorticate rigidity is characterized by flexion of the elbows and wrists with extension of the legs and feet. The causative lesion for this condition is located above the red nuclei and usually consists of diffuse cerebral damage. (From Adams et al., Principles of Neurology, 6th ed, p358)
The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.
An enzyme of the lyase class that catalyzes the formation of CYCLIC AMP and pyrophosphate from ATP. EC 4.6.1.1.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.

Effect of morphine and naloxone on priming-induced audiogenic seizures in BALB/c mice. (1/6631)

1 Morphine (1-200 mg/kg s.c.) reduced the incidence and prolonged the latency of priming-induced audiogenic siezures in a dose-dependent manner. 2 This effect was reversed by naloxone (1 and 2 mg/kg) although naloxone was itself inactive. 3 This priming-induces seizure model may be useful in the study of tolerance and physical dependence.  (+info)

The functional anatomy of the normal human auditory system: responses to 0.5 and 4.0 kHz tones at varied intensities. (2/6631)

Most functional imaging studies of the auditory system have employed complex stimuli. We used positron emission tomography to map neural responses to 0.5 and 4.0 kHz sine-wave tones presented to the right ear at 30, 50, 70 and 90 dB HL and found activation in a complex neural network of elements traditionally associated with the auditory system as well as non-traditional sites such as the posterior cingulate cortex. Cingulate activity was maximal at low stimulus intensities, suggesting that it may function as a gain control center. In the right temporal lobe, the location of the maximal response varied with the intensity, but not with the frequency of the stimuli. In the left temporal lobe, there was evidence for tonotopic organization: a site lateral to the left primary auditory cortex was activated equally by both tones while a second site in primary auditory cortex was more responsive to the higher frequency. Infratentorial activations were contralateral to the stimulated ear and included the lateral cerebellum, the lateral pontine tegmentum, the midbrain and the medial geniculate. Contrary to predictions based on cochlear membrane mechanics, at each intensity, 4.0 kHz stimuli were more potent activators of the brain than the 0.5 kHz stimuli.  (+info)

The effects of d-amphetamine on the temporal control of operant responding in rats during a preshock stimulus. (3/6631)

The operant behavior of six rats was maintained by a random-interval schedule of reinforcement. Three-minute periods of noise were superimposed on this behavior, each period ending with the delivery of an unavoidable shock. Overall rates of responding were generally lower during the periods of noise than in its absence (conditioned suppression). These suppressed response rates also exhibited temporal patterning, with responding becoming less frequent as each noise period progressed. The effects of d-amphetamine on this behavioral baseline were then assessed. In four animals the relative response rates during the noise and in its absence suggested that the drug produced a dose-related decrease in the amount of conditioned suppression. However, this effect was often due to a decrease in the rates of responding in the absence of the preshock stimulus, rather than to an increase in response rates during the stimulus. Temporal patterning in response rates during the preshock stimulus was abolished, an effect that was interpreted in terms of rate-dependent effect of d-amphetamine. This study thus extends rate-dependent analyses of the effects of amphetamines to the patterns of operant behavior that occur during a preshock stimulus, and which have been discussed in terms of the disrupting effects of anxiety on operant behavior.  (+info)

Midbrain combinatorial code for temporal and spectral information in concurrent acoustic signals. (4/6631)

All vocal species, including humans, often encounter simultaneous (concurrent) vocal signals from conspecifics. To segregate concurrent signals, the auditory system must extract information regarding the individual signals from their summed waveforms. During the breeding season, nesting male midshipman fish (Porichthys notatus) congregate in localized regions of the intertidal zone and produce long-duration (>1 min), multi-harmonic signals ("hums") during courtship of females. The hums of neighboring males often overlap, resulting in acoustic beats with amplitude and phase modulations at the difference frequencies (dFs) between their fundamental frequencies (F0s) and harmonic components. Behavioral studies also show that midshipman can localize a single hum-like tone when presented with a choice between two concurrent tones that originate from separate speakers. A previous study of the neural mechanisms underlying the segregation of concurrent signals demonstrated that midbrain neurons temporally encode a beat's dF through spike synchronization; however, spectral information about at least one of the beat's components is also required for signal segregation. Here we examine the encoding of spectral differences in beat signals by midbrain neurons. The results show that, although the spike rate responses of many neurons are sensitive to the spectral composition of a beat, virtually all midbrain units can encode information about differences in the spectral composition of beat stimuli via their interspike intervals (ISIs) with an equal distribution of ISI spectral sensitivity across the behaviorally relevant dFs. Together, temporal encoding in the midbrain of dF information through spike synchronization and of spectral information through ISI could permit the segregation of concurrent vocal signals.  (+info)

Desynchronizing responses to correlated noise: A mechanism for binaural masking level differences at the inferior colliculus. (5/6631)

We examined the adequacy of decorrelation of the responses to dichotic noise as an explanation for the binaural masking level difference (BMLD). The responses of 48 low-frequency neurons in the inferior colliculus of anesthetized guinea pigs were recorded to binaurally presented noise with various degrees of interaural correlation and to interaurally correlated noise in the presence of 500-Hz tones in either zero or pi interaural phase. In response to fully correlated noise, neurons' responses were modulated with interaural delay, showing quasiperiodic noise delay functions (NDFs) with a central peak and side peaks, separated by intervals roughly equivalent to the period of the neuron's best frequency. For noise with zero interaural correlation (independent noises presented to each ear), neurons were insensitive to the interaural delay. Their NDFs were unmodulated, with the majority showing a level of activity approximately equal to the mean of the peaks and troughs of the NDF obtained with fully correlated noise. Partial decorrelation of the noise resulted in NDFs that were, in general, intermediate between the fully correlated and fully decorrelated noise. Presenting 500-Hz tones simultaneously with fully correlated noise also had the effect of demodulating the NDFs. In the case of tones with zero interaural phase, this demodulation appeared to be a saturation process, raising the discharge at all noise delays to that at the largest peak in the NDF. In the majority of neurons, presenting the tones in pi phase had a similar effect on the NDFs to decorrelating the noise; the response was demodulated toward the mean of the peaks and troughs of the NDF. Thus the effect of added tones on the responses of delay-sensitive inferior colliculus neurons to noise could be accounted for by a desynchronizing effect. This result is entirely consistent with cross-correlation models of the BMLD. However, in some neurons, the effects of an added tone on the NDF appeared more extreme than the effect of decorrelating the noise, suggesting the possibility of additional inhibitory influences.  (+info)

Corticofugal amplification of facilitative auditory responses of subcortical combination-sensitive neurons in the mustached bat. (6/6631)

Recent studies on the bat's auditory system indicate that the corticofugal system mediates a highly focused positive feedback to physiologically "matched" subcortical neurons, and widespread lateral inhibition to physiologically "unmatched" subcortical neurons, to adjust and improve information processing. These findings have solved the controversy in physiological data, accumulated since 1962, of corticofugal effects on subcortical auditory neurons: inhibitory, excitatory, or both (an inhibitory effect is much more frequent than an excitatory effect). In the mustached bat, Pteronotus parnellii parnellii, the inferior colliculus, medial geniculate body, and auditory cortex each have "FM-FM" neurons, which are "combination-sensitive" and are tuned to specific time delays (echo delays) of echo FM components from the FM components of an emitted biosonar pulse. FM-FM neurons are more complex in response properties than cortical neurons which primarily respond to single tones. In the present study, we found that inactivation of the entire FM-FM area in the cortex, including neurons both physiologically matched and unmatched with subcortical FM-FM neurons, on the average reduced the facilitative responses to paired FM sounds by 82% for thalamic FM-FM neurons and by 66% for collicular FM-FM neurons. The corticofugal influence on the facilitative responses of subcortical combination-sensitive neurons is much larger than that on the excitatory responses of subcortical neurons primarily responding to single tones. Therefore we propose the hypothesis that, in general, the processing of complex sounds by combination-sensitive neurons more heavily depends on the corticofugal system than that by single-tone sensitive neurons.  (+info)

Effects of chronic administration of kanamycin on conditioned suppression to auditory stimulus in rats. (7/6631)

The conditioned suppression technique was employed to study the ototoxic effects of chronic administration of the antibiotic, kanamycin. Lever pressing behavior for food reinforcement of rats was suppressed in the presence of an auditory stimulus (sound) or visual stimulus (light) that had been previously paired with electric shocks. Repeated administration of kanamycin at the dose of 400 mg/kg/day for more than 50 days significantly attenuated the conditioned suppression to auditory stimulus but did not attenuate the conditioned suppression to visual stimulus. This finding suggests that the attenuating effect of chronic administration of kanamycin on conditioned suppression to auditory stimulus can be interpreted in terms of the selective action of the drug on the auditory system.  (+info)

Blockade of N-methyl-D-aspartate receptor activation suppresses learning-induced synaptic elimination. (8/6631)

Auditory filial imprinting in the domestic chicken is accompanied by a dramatic loss of spine synapses in two higher associative forebrain areas, the mediorostral neostriatum/hyperstriatum ventrale (MNH) and the dorsocaudal neostriatum (Ndc). The cellular mechanisms that underlie this learning-induced synaptic reorganization are unclear. We found that local pharmacological blockade of N-methyl-D-aspartate (NMDA) receptors in the MNH, a manipulation that has been shown previously to impair auditory imprinting, suppresses the learning-induced spine reduction in this region. Chicks treated with the NMDA receptor antagonist 2-amino-5-phosphonovaleric acid (APV) during the behavioral training for imprinting (postnatal day 0-2) displayed similar spine frequencies at postnatal day 7 as naive control animals, which, in both groups, were significantly higher than in imprinted animals. Because the average dendritic length did not differ between the experimental groups, the reduced spine frequency can be interpreted as a reduction of the total number of spine synapses per neuron. In the Ndc, which is reciprocally connected with the MNH and not directly influenced by the injected drug, learning-induced spine elimination was partly suppressed. Spine frequencies of the APV-treated, behaviorally trained but nonimprinted animals were higher than in the imprinted animals but lower than in the naive animals. These results provide evidence that NMDA receptor activation is required for the learning-induced selective reduction of spine synapses, which may serve as a mechanism of information storage specific for juvenile emotional learning events.  (+info)

Acoustic stimulation refers to the use of sound waves or vibrations to elicit a response in an individual, typically for the purpose of assessing or treating hearing, balance, or neurological disorders. In a medical context, acoustic stimulation may involve presenting pure tones, speech sounds, or other types of auditory signals through headphones, speakers, or specialized devices such as bone conduction transducers.

The response to acoustic stimulation can be measured using various techniques, including electrophysiological tests like auditory brainstem responses (ABRs) or otoacoustic emissions (OAEs), behavioral observations, or functional imaging methods like fMRI. Acoustic stimulation is also used in therapeutic settings, such as auditory training programs for hearing impairment or vestibular rehabilitation for balance disorders.

It's important to note that acoustic stimulation should be administered under the guidance of a qualified healthcare professional to ensure safety and effectiveness.

The auditory threshold is the minimum sound intensity or loudness level that a person can detect 50% of the time, for a given tone frequency. It is typically measured in decibels (dB) and represents the quietest sound that a person can hear. The auditory threshold can be affected by various factors such as age, exposure to noise, and certain medical conditions. Hearing tests, such as pure-tone audiometry, are used to measure an individual's auditory thresholds for different frequencies.

The cochlea is a part of the inner ear that is responsible for hearing. It is a spiral-shaped structure that looks like a snail shell and is filled with fluid. The cochlea contains hair cells, which are specialized sensory cells that convert sound vibrations into electrical signals that are sent to the brain.

The cochlea has three main parts: the vestibular canal, the tympanic canal, and the cochlear duct. Sound waves enter the inner ear and cause the fluid in the cochlea to move, which in turn causes the hair cells to bend. This bending motion stimulates the hair cells to generate electrical signals that are sent to the brain via the auditory nerve.

The brain then interprets these signals as sound, allowing us to hear and understand speech, music, and other sounds in our environment. Damage to the hair cells or other structures in the cochlea can lead to hearing loss or deafness.

Electric stimulation, also known as electrical nerve stimulation or neuromuscular electrical stimulation, is a therapeutic treatment that uses low-voltage electrical currents to stimulate nerves and muscles. It is often used to help manage pain, promote healing, and improve muscle strength and mobility. The electrical impulses can be delivered through electrodes placed on the skin or directly implanted into the body.

In a medical context, electric stimulation may be used for various purposes such as:

1. Pain management: Electric stimulation can help to block pain signals from reaching the brain and promote the release of endorphins, which are natural painkillers produced by the body.
2. Muscle rehabilitation: Electric stimulation can help to strengthen muscles that have become weak due to injury, illness, or surgery. It can also help to prevent muscle atrophy and improve range of motion.
3. Wound healing: Electric stimulation can promote tissue growth and help to speed up the healing process in wounds, ulcers, and other types of injuries.
4. Urinary incontinence: Electric stimulation can be used to strengthen the muscles that control urination and reduce symptoms of urinary incontinence.
5. Migraine prevention: Electric stimulation can be used as a preventive treatment for migraines by applying electrical impulses to specific nerves in the head and neck.

It is important to note that electric stimulation should only be administered under the guidance of a qualified healthcare professional, as improper use can cause harm or discomfort.

Hearing is the ability to perceive sounds by detecting vibrations in the air or other mediums and translating them into nerve impulses that are sent to the brain for interpretation. In medical terms, hearing is defined as the sense of sound perception, which is mediated by the ear and interpreted by the brain. It involves a complex series of processes, including the conduction of sound waves through the outer ear to the eardrum, the vibration of the middle ear bones, and the movement of fluid in the inner ear, which stimulates hair cells to send electrical signals to the auditory nerve and ultimately to the brain. Hearing allows us to communicate with others, appreciate music and sounds, and detect danger or important events in our environment.

Cochlear implants are medical devices that are surgically implanted in the inner ear to help restore hearing in individuals with severe to profound hearing loss. These devices bypass the damaged hair cells in the inner ear and directly stimulate the auditory nerve, allowing the brain to interpret sound signals. Cochlear implants consist of two main components: an external processor that picks up and analyzes sounds from the environment, and an internal receiver/stimulator that receives the processed information and sends electrical impulses to the auditory nerve. The resulting patterns of electrical activity are then perceived as sound by the brain. Cochlear implants can significantly improve communication abilities, language development, and overall quality of life for individuals with profound hearing loss.

Hearing aids are electronic devices designed to improve hearing and speech comprehension for individuals with hearing loss. They consist of a microphone, an amplifier, a speaker, and a battery. The microphone picks up sounds from the environment, the amplifier increases the volume of these sounds, and the speaker sends the amplified sound into the ear. Modern hearing aids often include additional features such as noise reduction, directional microphones, and wireless connectivity to smartphones or other devices. They are programmed to meet the specific needs of the user's hearing loss and can be adjusted for comfort and effectiveness. Hearing aids are available in various styles, including behind-the-ear (BTE), receiver-in-canal (RIC), in-the-ear (ITE), and completely-in-canal (CIC).

Auditory pathways refer to the series of structures and nerves in the body that are involved in processing sound and transmitting it to the brain for interpretation. The process begins when sound waves enter the ear and cause vibrations in the eardrum, which then move the bones in the middle ear. These movements stimulate hair cells in the cochlea, a spiral-shaped structure in the inner ear, causing them to release neurotransmitters that activate auditory nerve fibers.

The auditory nerve carries these signals to the brainstem, where they are relayed through several additional structures before reaching the auditory cortex in the temporal lobe of the brain. Here, the signals are processed and interpreted as sounds, allowing us to hear and understand speech, music, and other environmental noises.

Damage or dysfunction at any point along the auditory pathway can lead to hearing loss or impairment.

Spontaneous otoacoustic emissions (SOAEs) are low-level sounds that are produced by the inner ear (cochlea) without any external stimulation. They can be recorded in a quiet room using specialized microphones placed inside the ear canal. SOAEs are thought to arise from the motion of the hair cells within the cochlea, which generate tiny currents in response to sound. These currents then cause the surrounding fluid and tissue to vibrate, producing sound waves that can be detected with a microphone.

SOAEs are typically present in individuals with normal hearing, although their presence or absence is not a definitive indicator of hearing ability. They tend to occur at specific frequencies and can vary from person to person. In some cases, SOAEs may be absent or reduced in individuals with hearing loss or damage to the hair cells in the cochlea.

It's worth noting that SOAEs are different from evoked otoacoustic emissions (EOAEs), which are sounds produced by the inner ear in response to external stimuli, such as clicks or tones. Both types of otoacoustic emissions are used in hearing tests and research to assess cochlear function and health.

Auditory evoked potentials (AEP) are medical tests that measure the electrical activity in the brain in response to sound stimuli. These tests are often used to assess hearing function and neural processing in individuals, particularly those who cannot perform traditional behavioral hearing tests.

There are several types of AEP tests, including:

1. Brainstem Auditory Evoked Response (BAER) or Brainstem Auditory Evoked Potentials (BAEP): This test measures the electrical activity generated by the brainstem in response to a click or tone stimulus. It is often used to assess the integrity of the auditory nerve and brainstem pathways, and can help diagnose conditions such as auditory neuropathy and retrocochlear lesions.
2. Middle Latency Auditory Evoked Potentials (MLAEP): This test measures the electrical activity generated by the cortical auditory areas of the brain in response to a click or tone stimulus. It is often used to assess higher-level auditory processing, and can help diagnose conditions such as auditory processing disorders and central auditory dysfunction.
3. Long Latency Auditory Evoked Potentials (LLAEP): This test measures the electrical activity generated by the cortical auditory areas of the brain in response to a complex stimulus, such as speech. It is often used to assess language processing and cognitive function, and can help diagnose conditions such as learning disabilities and dementia.

Overall, AEP tests are valuable tools for assessing hearing and neural function in individuals who cannot perform traditional behavioral hearing tests or who have complex neurological conditions.

Speech Audiometry is a hearing test that measures a person's ability to understand and recognize spoken words at different volumes and frequencies. It is used to assess the function of the auditory system, particularly in cases where there is a suspected problem with speech discrimination or understanding spoken language.

The test typically involves presenting lists of words to the patient at varying intensity levels and asking them to repeat what they hear. The examiner may also present sentences with missing words that the patient must fill in. Based on the results, the audiologist can determine the quietest level at which the patient can reliably detect speech and the degree of speech discrimination ability.

Speech Audiometry is often used in conjunction with pure-tone audiometry to provide a more comprehensive assessment of hearing function. It can help identify any specific patterns of hearing loss, such as those caused by nerve damage or cochlear dysfunction, and inform decisions about treatment options, including the need for hearing aids or other assistive devices.

Auditory brainstem evoked potentials (ABEPs or BAEPs) are medical tests that measure the electrical activity in the auditory pathway of the brain in response to sound stimulation. The test involves placing electrodes on the scalp and recording the tiny electrical signals generated by the nerve cells in the brainstem as they respond to clicks or tone bursts presented through earphones.

The resulting waveform is analyzed for latency (the time it takes for the signal to travel from the ear to the brain) and amplitude (the strength of the signal). Abnormalities in the waveform can indicate damage to the auditory nerve or brainstem, and are often used in the diagnosis of various neurological conditions such as multiple sclerosis, acoustic neuroma, and brainstem tumors.

The test is non-invasive, painless, and takes only a few minutes to perform. It provides valuable information about the functioning of the auditory pathway and can help guide treatment decisions for patients with hearing or balance disorders.

The auditory cortex is the region of the brain that is responsible for processing and analyzing sounds, including speech. It is located in the temporal lobe of the cerebral cortex, specifically within the Heschl's gyrus and the surrounding areas. The auditory cortex receives input from the auditory nerve, which carries sound information from the inner ear to the brain.

The auditory cortex is divided into several subregions that are responsible for different aspects of sound processing, such as pitch, volume, and location. These regions work together to help us recognize and interpret sounds in our environment, allowing us to communicate with others and respond appropriately to our surroundings. Damage to the auditory cortex can result in hearing loss or difficulty understanding speech.

Deafness is a hearing loss that is so severe that it results in significant difficulty in understanding or comprehending speech, even when using hearing aids. It can be congenital (present at birth) or acquired later in life due to various causes such as disease, injury, infection, exposure to loud noises, or aging. Deafness can range from mild to profound and may affect one ear (unilateral) or both ears (bilateral). In some cases, deafness may be accompanied by tinnitus, which is the perception of ringing or other sounds in the ears.

Deaf individuals often use American Sign Language (ASL) or other forms of sign language to communicate. Some people with less severe hearing loss may benefit from hearing aids, cochlear implants, or other assistive listening devices. Deafness can have significant social, educational, and vocational implications, and early intervention and appropriate support services are critical for optimal development and outcomes.

Cochlear implantation is a surgical procedure in which a device called a cochlear implant is inserted into the inner ear (cochlea) of a person with severe to profound hearing loss. The implant consists of an external component, which includes a microphone, processor, and transmitter, and an internal component, which includes a receiver and electrode array.

The microphone picks up sounds from the environment and sends them to the processor, which analyzes and converts the sounds into electrical signals. These signals are then transmitted to the receiver, which stimulates the electrode array in the cochlea. The electrodes directly stimulate the auditory nerve fibers, bypassing the damaged hair cells in the inner ear that are responsible for normal hearing.

The brain interprets these electrical signals as sound, allowing the person to perceive and understand speech and other sounds. Cochlear implantation is typically recommended for people who do not benefit from traditional hearing aids and can significantly improve communication, quality of life, and social integration for those with severe to profound hearing loss.

The cochlear nerve, also known as the auditory nerve, is the sensory nerve that transmits sound signals from the inner ear to the brain. It consists of two parts: the outer spiral ganglion and the inner vestibular portion. The spiral ganglion contains the cell bodies of the bipolar neurons that receive input from hair cells in the cochlea, which is the snail-shaped organ in the inner ear responsible for hearing. These neurons then send their axons to form the cochlear nerve, which travels through the internal auditory meatus and synapses with neurons in the cochlear nuclei located in the brainstem.

Damage to the cochlear nerve can result in hearing loss or deafness, depending on the severity of the injury. Common causes of cochlear nerve damage include acoustic trauma, such as exposure to loud noises, viral infections, meningitis, and tumors affecting the nerve or surrounding structures. In some cases, cochlear nerve damage may be treated with hearing aids, cochlear implants, or other assistive devices to help restore or improve hearing function.

In the context of medicine, particularly in audiology and otolaryngology (ear, nose, and throat specialty), "noise" is defined as unwanted or disturbing sound in the environment that can interfere with communication, rest, sleep, or cognitive tasks. It can also refer to sounds that are harmful to hearing, such as loud machinery noises or music, which can cause noise-induced hearing loss if exposure is prolonged or at high enough levels.

In some medical contexts, "noise" may also refer to non-specific signals or interfering factors in diagnostic tests and measurements that can make it difficult to interpret results accurately.

The tympanic membrane, also known as the eardrum, is a thin, cone-shaped membrane that separates the external auditory canal from the middle ear. It serves to transmit sound vibrations from the air to the inner ear, where they are converted into electrical signals that can be interpreted by the brain as sound. The tympanic membrane is composed of three layers: an outer layer of skin, a middle layer of connective tissue, and an inner layer of mucous membrane. It is held in place by several small bones and muscles and is highly sensitive to changes in pressure.

Hearing loss is a partial or total inability to hear sounds in one or both ears. It can occur due to damage to the structures of the ear, including the outer ear, middle ear, inner ear, or nerve pathways that transmit sound to the brain. The degree of hearing loss can vary from mild (difficulty hearing soft sounds) to severe (inability to hear even loud sounds). Hearing loss can be temporary or permanent and may be caused by factors such as exposure to loud noises, genetics, aging, infections, trauma, or certain medical conditions. It is important to note that hearing loss can have significant impacts on a person's communication abilities, social interactions, and overall quality of life.

Psychoacoustics is a branch of psychophysics that deals with the study of the psychological and physiological responses to sound. It involves understanding how people perceive, interpret, and react to different sounds, including speech, music, and environmental noises. This field combines knowledge from various areas such as psychology, acoustics, physics, and engineering to investigate the relationship between physical sound characteristics and human perception. Research in psychoacoustics has applications in fields like hearing aid design, noise control, music perception, and communication systems.

Sound spectrography, also known as voice spectrography, is a diagnostic procedure in which a person's speech sounds are analyzed and displayed as a visual pattern called a spectrogram. This test is used to evaluate voice disorders, speech disorders, and hearing problems. It can help identify patterns of sound production and reveal any abnormalities in the vocal tract or hearing mechanism.

During the test, a person is asked to produce specific sounds or sentences, which are then recorded and analyzed by a computer program. The program breaks down the sound waves into their individual frequencies and amplitudes, and displays them as a series of horizontal lines on a graph. The resulting spectrogram shows how the frequencies and amplitudes change over time, providing valuable information about the person's speech patterns and any underlying problems.

Sound spectrography is a useful tool for diagnosing and treating voice and speech disorders, as well as for researching the acoustic properties of human speech. It can also be used to evaluate hearing aids and other assistive listening devices, and to assess the effectiveness of various treatments for hearing loss and other auditory disorders.

Efferent pathways refer to the neural connections that carry signals from the central nervous system (CNS), which includes the brain and spinal cord, to the peripheral effectors such as muscles and glands. These pathways are responsible for the initiation and control of motor responses, as well as regulating various autonomic functions.

Efferent pathways can be divided into two main types:

1. Somatic efferent pathways: These pathways carry signals from the CNS to the skeletal muscles, enabling voluntary movements and postural control. The final common pathway for somatic motor innervation is the alpha-motor neuron, which synapses directly onto skeletal muscle fibers.
2. Autonomic efferent pathways: These pathways regulate the function of internal organs, smooth muscles, and glands. They are further divided into two subtypes: sympathetic and parasympathetic. The sympathetic system is responsible for the 'fight or flight' response, while the parasympathetic system promotes rest and digestion. Both systems use a two-neuron chain to transmit signals from the CNS to the effector organs. The preganglionic neuron has its cell body in the CNS and synapses with the postganglionic neuron in an autonomic ganglion located near the effector organ. The postganglionic neuron then innervates the target organ or tissue.

In summary, efferent pathways are the neural connections that carry signals from the CNS to peripheral effectors, enabling motor responses and regulating various autonomic functions. They can be divided into somatic and autonomic efferent pathways, with further subdivisions within the autonomic system.

Speech perception is the process by which the brain interprets and understands spoken language. It involves recognizing and discriminating speech sounds (phonemes), organizing them into words, and attaching meaning to those words in order to comprehend spoken language. This process requires the integration of auditory information with prior knowledge and context. Factors such as hearing ability, cognitive function, and language experience can all impact speech perception.

Sound localization is the ability of the auditory system to identify the location or origin of a sound source in the environment. It is a crucial aspect of hearing and enables us to navigate and interact with our surroundings effectively. The process involves several cues, including time differences in the arrival of sound to each ear (interaural time difference), differences in sound level at each ear (interaural level difference), and spectral information derived from the filtering effects of the head and external ears on incoming sounds. These cues are analyzed by the brain to determine the direction and distance of the sound source, allowing for accurate localization.

The inferior colliculi are a pair of rounded eminences located in the midbrain, specifically in the tectum of the mesencephalon. They play a crucial role in auditory processing and integration. The inferior colliculi receive inputs from various sources, including the cochlear nuclei, superior olivary complex, and cortical areas. They then send their outputs to the medial geniculate body, which is a part of the thalamus that relays auditory information to the auditory cortex.

In summary, the inferior colliculi are important structures in the auditory pathway that help process and integrate auditory information before it reaches the cerebral cortex for further analysis and perception.

The olivary nucleus is a structure located in the medulla oblongata, which is a part of the brainstem. It consists of two main parts: the inferior olive and the accessory olive. The inferior olive is further divided into several subnuclei.

The olivary nucleus plays an important role in the coordination of movements, particularly in the regulation of fine motor control and rhythmic movements. It receives input from various sources, including the cerebellum, spinal cord, and other brainstem nuclei, and sends output to the cerebellum via the climbing fibers.

Damage to the olivary nucleus can result in a variety of neurological symptoms, including ataxia (loss of coordination), tremors, and dysarthria (speech difficulties). Certain neurodegenerative disorders, such as multiple system atrophy, may also affect the olivary nucleus and contribute to its degeneration.

The cochlear nucleus is the first relay station in the auditory pathway within the central nervous system. It is a structure located in the lower pons region of the brainstem and receives sensory information from the cochlea, which is the spiral-shaped organ of hearing in the inner ear.

The cochlear nucleus consists of several subdivisions, each with distinct neuronal populations that process different aspects of auditory information. These subdivisions include the anteroventral cochlear nucleus (AVCN), posteroventral cochlear nucleus (PVCN), dorsal cochlear nucleus (DCN), and the granule cell domain.

Neurons in these subdivisions perform various computations on the incoming auditory signals, such as frequency analysis, intensity coding, and sound localization. The output of the cochlear nucleus is then sent via several pathways to higher brain regions for further processing and interpretation, including the inferior colliculus, medial geniculate body, and eventually the auditory cortex.

Damage or dysfunction in the cochlear nucleus can lead to hearing impairments and other auditory processing disorders.

Audiometry is the testing of a person's ability to hear different sounds, pitches, or frequencies. It is typically conducted using an audiometer, a device that emits tones at varying volumes and frequencies. The person being tested wears headphones and indicates when they can hear the tone by pressing a button or raising their hand.

There are two main types of audiometry: pure-tone audiometry and speech audiometry. Pure-tone audiometry measures a person's ability to hear different frequencies at varying volumes, while speech audiometry measures a person's ability to understand spoken words at different volumes and in the presence of background noise.

The results of an audiometry test are typically plotted on an audiogram, which shows the quietest sounds that a person can hear at different frequencies. This information can be used to diagnose hearing loss, determine its cause, and develop a treatment plan.

Auditory outer hair cells are specialized sensory receptor cells located in the cochlea of the inner ear. They are part of the organ of Corti and play a crucial role in hearing by converting sound energy into electrical signals that can be interpreted by the brain.

Unlike the more numerous and simpler auditory inner hair cells, outer hair cells are equipped with unique actin-based molecular motors called "motile" or "piezoelectric" properties. These motors enable the outer hair cells to change their shape and length in response to electrical signals, which in turn amplifies the mechanical vibrations of the basilar membrane where they are located. This amplification increases the sensitivity and frequency selectivity of hearing, allowing us to detect and discriminate sounds over a wide range of intensities and frequencies.

Damage or loss of outer hair cells is a common cause of sensorineural hearing loss, which can result from exposure to loud noises, aging, genetics, ototoxic drugs, and other factors. Currently, there are no effective treatments to regenerate or replace damaged outer hair cells, making hearing loss an irreversible condition in most cases.

Pure-tone audiometry is a hearing test that measures a person's ability to hear different sounds, pitches, or frequencies. During the test, pure tones are presented to the patient through headphones or ear inserts, and the patient is asked to indicate each time they hear the sound by raising their hand, pressing a button, or responding verbally.

The softest sound that the person can hear at each frequency is recorded as the hearing threshold, and a graph called an audiogram is created to show the results. The audiogram provides information about the type and degree of hearing loss in each ear. Pure-tone audiometry is a standard hearing test used to diagnose and monitor hearing disorders.

Auditory perception refers to the process by which the brain interprets and makes sense of the sounds we hear. It involves the recognition and interpretation of different frequencies, intensities, and patterns of sound waves that reach our ears through the process of hearing. This allows us to identify and distinguish various sounds such as speech, music, and environmental noises.

The auditory system includes the outer ear, middle ear, inner ear, and the auditory nerve, which transmits electrical signals to the brain's auditory cortex for processing and interpretation. Auditory perception is a complex process that involves multiple areas of the brain working together to identify and make sense of sounds in our environment.

Disorders or impairments in auditory perception can result in difficulties with hearing, understanding speech, and identifying environmental sounds, which can significantly impact communication, learning, and daily functioning.

Auditory hair cells are specialized sensory receptor cells located in the inner ear, more specifically in the organ of Corti within the cochlea. They play a crucial role in hearing by converting sound vibrations into electrical signals that can be interpreted by the brain.

These hair cells have hair-like projections called stereocilia on their apical surface, which are embedded in a gelatinous matrix. When sound waves reach the inner ear, they cause the fluid within the cochlea to move, which in turn causes the stereocilia to bend. This bending motion opens ion channels at the tips of the stereocilia, allowing positively charged ions (such as potassium) to flow into the hair cells and trigger a receptor potential.

The receptor potential then leads to the release of neurotransmitters at the base of the hair cells, which activate afferent nerve fibers that synapse with these cells. The electrical signals generated by this process are transmitted to the brain via the auditory nerve, where they are interpreted as sound.

There are two types of auditory hair cells: inner hair cells and outer hair cells. Inner hair cells are the primary sensory receptors responsible for transmitting information about sound to the brain. They make direct contact with afferent nerve fibers and are more sensitive to mechanical stimulation than outer hair cells.

Outer hair cells, on the other hand, are involved in amplifying and fine-tuning the mechanical response of the inner ear to sound. They have a unique ability to contract and relax in response to electrical signals, which allows them to adjust the stiffness of their stereocilia and enhance the sensitivity of the cochlea to different frequencies.

Damage or loss of auditory hair cells can lead to hearing impairment or deafness, as these cells cannot regenerate spontaneously in mammals. Therefore, understanding the structure and function of hair cells is essential for developing therapies aimed at treating hearing disorders.

Gerbillinae is a subfamily of rodents that includes gerbils, jirds, and sand rats. These small mammals are primarily found in arid regions of Africa and Asia. They are characterized by their long hind legs, which they use for hopping, and their long, thin tails. Some species have adapted to desert environments by developing specialized kidneys that allow them to survive on minimal water intake.

I must clarify that the term "Guinea Pigs" is not typically used in medical definitions. However, in colloquial or informal language, it may refer to people who are used as the first to try out a new medical treatment or drug. This is known as being a "test subject" or "in a clinical trial."

In the field of scientific research, particularly in studies involving animals, guinea pigs are small rodents that are often used as experimental subjects due to their size, cost-effectiveness, and ease of handling. They are not actually pigs from Guinea, despite their name's origins being unclear. However, they do not exactly fit the description of being used in human medical experiments.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Electric stimulation therapy, also known as neuromuscular electrical stimulation (NMES) or electromyostimulation, is a therapeutic treatment that uses electrical impulses to stimulate muscles and nerves. The electrical signals are delivered through electrodes placed on the skin near the target muscle group or nerve.

The therapy can be used for various purposes, including:

1. Pain management: Electric stimulation can help reduce pain by stimulating the release of endorphins, which are natural painkillers produced by the body. It can also help block the transmission of pain signals to the brain.
2. Muscle rehabilitation: NMES can be used to prevent muscle atrophy and maintain muscle tone in individuals who are unable to move their muscles due to injury or illness, such as spinal cord injuries or stroke.
3. Improving circulation: Electric stimulation can help improve blood flow and reduce swelling by contracting the muscles and promoting the movement of fluids in the body.
4. Wound healing: NMES can be used to promote wound healing by increasing blood flow, reducing swelling, and improving muscle function around the wound site.
5. Muscle strengthening: Electric stimulation can be used to strengthen muscles by causing them to contract and relax repeatedly, which can help improve muscle strength and endurance.

It is important to note that electric stimulation therapy should only be administered under the guidance of a trained healthcare professional, as improper use can cause harm or discomfort.

Functional laterality, in a medical context, refers to the preferential use or performance of one side of the body over the other for specific functions. This is often demonstrated in hand dominance, where an individual may be right-handed or left-handed, meaning they primarily use their right or left hand for tasks such as writing, eating, or throwing.

However, functional laterality can also apply to other bodily functions and structures, including the eyes (ocular dominance), ears (auditory dominance), or legs. It's important to note that functional laterality is not a strict binary concept; some individuals may exhibit mixed dominance or no strong preference for one side over the other.

In clinical settings, assessing functional laterality can be useful in diagnosing and treating various neurological conditions, such as stroke or traumatic brain injury, where understanding any resulting lateralized impairments can inform rehabilitation strategies.

A chemical stimulation in a medical context refers to the process of activating or enhancing physiological or psychological responses in the body using chemical substances. These chemicals can interact with receptors on cells to trigger specific reactions, such as neurotransmitters and hormones that transmit signals within the nervous system and endocrine system.

Examples of chemical stimulation include the use of medications, drugs, or supplements that affect mood, alertness, pain perception, or other bodily functions. For instance, caffeine can chemically stimulate the central nervous system to increase alertness and decrease feelings of fatigue. Similarly, certain painkillers can chemically stimulate opioid receptors in the brain to reduce the perception of pain.

It's important to note that while chemical stimulation can have therapeutic benefits, it can also have adverse effects if used improperly or in excessive amounts. Therefore, it's essential to follow proper dosing instructions and consult with a healthcare provider before using any chemical substances for stimulation purposes.

Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.

Deep brain stimulation (DBS) is a surgical procedure that involves the implantation of a medical device called a neurostimulator, which sends electrical impulses to specific targets in the brain. The impulses help to regulate abnormal brain activity, and can be used to treat a variety of neurological conditions, including Parkinson's disease, essential tremor, dystonia, and obsessive-compulsive disorder.

During the procedure, electrodes are implanted into the brain and connected to the neurostimulator, which is typically implanted in the chest. The neurostimulator can be programmed to deliver electrical impulses at varying frequencies, amplitudes, and pulse widths, depending on the specific needs of the patient.

DBS is generally considered a safe and effective treatment option for many patients with neurological conditions, although it does carry some risks, such as infection, bleeding, and hardware complications. It is typically reserved for patients who have not responded well to other forms of treatment, or who experience significant side effects from medication.

Physical stimulation, in a medical context, refers to the application of external forces or agents to the body or its tissues to elicit a response. This can include various forms of touch, pressure, temperature, vibration, or electrical currents. The purpose of physical stimulation may be therapeutic, as in the case of massage or physical therapy, or diagnostic, as in the use of reflex tests. It is also used in research settings to study physiological responses and mechanisms.

In a broader sense, physical stimulation can also refer to the body's exposure to physical activity or exercise, which can have numerous health benefits, including improving cardiovascular function, increasing muscle strength and flexibility, and reducing the risk of chronic diseases.

Transcranial Magnetic Stimulation (TMS) is a non-invasive form of brain stimulation where a magnetic field is generated via an electromagnetic coil placed on the scalp. This magnetic field induces an electric current in the underlying brain tissue, which can lead to neuronal activation or inhibition, depending on the frequency and intensity of the stimulation. TMS has been used as a therapeutic intervention for various neurological and psychiatric conditions, such as depression, migraine, and tinnitus, among others. It is also used in research settings to investigate brain function and connectivity.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Transcutaneous Electrical Nerve Stimulation (TENS) is a non-invasive method of pain relief that involves the use of low-voltage electrical currents. A TENS device, which is usually small and portable, delivers these currents through electrodes that are placed on the skin near the site of pain. The electrical impulses stimulate nerve fibers, which can help to block the transmission of pain signals to the brain, thereby reducing the perception of pain.

TENS is thought to work through a number of different mechanisms, including the gate control theory of pain and the release of endorphins, which are natural painkillers produced by the body. It is generally considered safe, with few side effects, and can be used in conjunction with other forms of pain management.

TENS is often used to treat chronic pain conditions such as arthritis, fibromyalgia, and lower back pain, as well as acute pain from injuries or surgery. However, its effectiveness varies from person to person, and it may not work for everyone. It is important to consult with a healthcare provider before using TENS, particularly if you have any underlying medical conditions or are taking medication that could interact with the electrical currents.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

"Cat" is a common name that refers to various species of small carnivorous mammals that belong to the family Felidae. The domestic cat, also known as Felis catus or Felis silvestris catus, is a popular pet and companion animal. It is a subspecies of the wildcat, which is found in Europe, Africa, and Asia.

Domestic cats are often kept as pets because of their companionship, playful behavior, and ability to hunt vermin. They are also valued for their ability to provide emotional support and therapy to people. Cats are obligate carnivores, which means that they require a diet that consists mainly of meat to meet their nutritional needs.

Cats are known for their agility, sharp senses, and predatory instincts. They have retractable claws, which they use for hunting and self-defense. Cats also have a keen sense of smell, hearing, and vision, which allow them to detect prey and navigate their environment.

In medical terms, cats can be hosts to various parasites and diseases that can affect humans and other animals. Some common feline diseases include rabies, feline leukemia virus (FeLV), feline immunodeficiency virus (FIV), and toxoplasmosis. It is important for cat owners to keep their pets healthy and up-to-date on vaccinations and preventative treatments to protect both the cats and their human companions.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Implanted electrodes are medical devices that are surgically placed inside the body to interface directly with nerves, neurons, or other electrically excitable tissue for various therapeutic purposes. These electrodes can be used to stimulate or record electrical activity from specific areas of the body, depending on their design and application.

There are several types of implanted electrodes, including:

1. Deep Brain Stimulation (DBS) electrodes: These are placed deep within the brain to treat movement disorders such as Parkinson's disease, essential tremor, and dystonia. DBS electrodes deliver electrical impulses that modulate abnormal neural activity in targeted brain regions.
2. Spinal Cord Stimulation (SCS) electrodes: These are implanted along the spinal cord to treat chronic pain syndromes. SCS electrodes emit low-level electrical pulses that interfere with pain signals traveling to the brain, providing relief for patients.
3. Cochlear Implant electrodes: These are surgically inserted into the cochlea of the inner ear to restore hearing in individuals with severe to profound hearing loss. The electrodes stimulate the auditory nerve directly, bypassing damaged hair cells within the cochlea.
4. Retinal Implant electrodes: These are implanted in the retina to treat certain forms of blindness caused by degenerative eye diseases like retinitis pigmentosa. The electrodes convert visual information from a camera into electrical signals, which stimulate remaining retinal cells and transmit the information to the brain via the optic nerve.
5. Sacral Nerve Stimulation (SNS) electrodes: These are placed near the sacral nerves in the lower back to treat urinary or fecal incontinence and overactive bladder syndrome. SNS electrodes deliver electrical impulses that regulate the function of the affected muscles and nerves.
6. Vagus Nerve Stimulation (VNS) electrodes: These are wrapped around the vagus nerve in the neck to treat epilepsy and depression. VNS electrodes provide intermittent electrical stimulation to the vagus nerve, which has connections to various regions of the brain involved in these conditions.

Overall, implanted electrodes serve as a crucial component in many neuromodulation therapies, offering an effective treatment option for numerous neurological and sensory disorders.

Muscle contraction is the physiological process in which muscle fibers shorten and generate force, leading to movement or stability of a body part. This process involves the sliding filament theory where thick and thin filaments within the sarcomeres (the functional units of muscles) slide past each other, facilitated by the interaction between myosin heads and actin filaments. The energy required for this action is provided by the hydrolysis of adenosine triphosphate (ATP). Muscle contractions can be voluntary or involuntary, and they play a crucial role in various bodily functions such as locomotion, circulation, respiration, and posture maintenance.

Photic stimulation is a medical term that refers to the exposure of the eyes to light, specifically repetitive pulses of light, which is used as a method in various research and clinical settings. In neuroscience, it's often used in studies related to vision, circadian rhythms, and brain function.

In a clinical context, photic stimulation is sometimes used in the diagnosis of certain medical conditions such as seizure disorders (like epilepsy). By observing the response of the brain to this light stimulus, doctors can gain valuable insights into the functioning of the brain and the presence of any neurological disorders.

However, it's important to note that photic stimulation should be conducted under the supervision of a trained healthcare professional, as improper use can potentially trigger seizures in individuals who are susceptible to them.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

An action potential is a brief electrical signal that travels along the membrane of a nerve cell (neuron) or muscle cell. It is initiated by a rapid, localized change in the permeability of the cell membrane to specific ions, such as sodium and potassium, resulting in a rapid influx of sodium ions and a subsequent efflux of potassium ions. This ion movement causes a brief reversal of the electrical potential across the membrane, which is known as depolarization. The action potential then propagates along the cell membrane as a wave, allowing the electrical signal to be transmitted over long distances within the body. Action potentials play a crucial role in the communication and functioning of the nervous system and muscle tissue.

Phosphorylation is the process of adding a phosphate group (a molecule consisting of one phosphorus atom and four oxygen atoms) to a protein or other organic molecule, which is usually done by enzymes called kinases. This post-translational modification can change the function, localization, or activity of the target molecule, playing a crucial role in various cellular processes such as signal transduction, metabolism, and regulation of gene expression. Phosphorylation is reversible, and the removal of the phosphate group is facilitated by enzymes called phosphatases.

The vagus nerve, also known as the 10th cranial nerve (CN X), is the longest of the cranial nerves and extends from the brainstem to the abdomen. It has both sensory and motor functions and plays a crucial role in regulating various bodily functions such as heart rate, digestion, respiratory rate, speech, and sweating, among others.

The vagus nerve is responsible for carrying sensory information from the internal organs to the brain, and it also sends motor signals from the brain to the muscles of the throat and voice box, as well as to the heart, lungs, and digestive tract. The vagus nerve helps regulate the body's involuntary responses, such as controlling heart rate and blood pressure, promoting relaxation, and reducing inflammation.

Dysfunction in the vagus nerve can lead to various medical conditions, including gastroparesis, chronic pain, and autonomic nervous system disorders. Vagus nerve stimulation (VNS) is a therapeutic intervention that involves delivering electrical impulses to the vagus nerve to treat conditions such as epilepsy, depression, and migraine headaches.

Enzyme activation refers to the process by which an enzyme becomes biologically active and capable of carrying out its specific chemical or biological reaction. This is often achieved through various post-translational modifications, such as proteolytic cleavage, phosphorylation, or addition of cofactors or prosthetic groups to the enzyme molecule. These modifications can change the conformation or structure of the enzyme, exposing or creating a binding site for the substrate and allowing the enzymatic reaction to occur.

For example, in the case of proteolytic cleavage, an inactive precursor enzyme, known as a zymogen, is cleaved into its active form by a specific protease. This is seen in enzymes such as trypsin and chymotrypsin, which are initially produced in the pancreas as inactive precursors called trypsinogen and chymotrypsinogen, respectively. Once they reach the small intestine, they are activated by enteropeptidase, a protease that cleaves a specific peptide bond, releasing the active enzyme.

Phosphorylation is another common mechanism of enzyme activation, where a phosphate group is added to a specific serine, threonine, or tyrosine residue on the enzyme by a protein kinase. This modification can alter the conformation of the enzyme and create a binding site for the substrate, allowing the enzymatic reaction to occur.

Enzyme activation is a crucial process in many biological pathways, as it allows for precise control over when and where specific reactions take place. It also provides a mechanism for regulating enzyme activity in response to various signals and stimuli, such as hormones, neurotransmitters, or changes in the intracellular environment.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Evoked potentials (EPs) are medical tests that measure the electrical activity in the brain or spinal cord in response to specific sensory stimuli, such as sight, sound, or touch. These tests are often used to help diagnose and monitor conditions that affect the nervous system, such as multiple sclerosis, brainstem tumors, and spinal cord injuries.

There are several types of EPs, including:

1. Visual Evoked Potentials (VEPs): These are used to assess the function of the visual pathway from the eyes to the back of the brain. A patient is typically asked to look at a patterned image or flashing light while electrodes placed on the scalp record the electrical responses.
2. Brainstem Auditory Evoked Potentials (BAEPs): These are used to evaluate the function of the auditory nerve and brainstem. Clicking sounds are presented to one or both ears, and electrodes placed on the scalp measure the response.
3. Somatosensory Evoked Potentials (SSEPs): These are used to assess the function of the peripheral nerves and spinal cord. Small electrical shocks are applied to a nerve at the wrist or ankle, and electrodes placed on the scalp record the response as it travels up the spinal cord to the brain.
4. Motor Evoked Potentials (MEPs): These are used to assess the function of the motor pathways in the brain and spinal cord. A magnetic or electrical stimulus is applied to the brain or spinal cord, and electrodes placed on a muscle measure the response as it travels down the motor pathway.

EPs can help identify abnormalities in the nervous system that may not be apparent through other diagnostic tests, such as imaging studies or clinical examinations. They are generally safe, non-invasive procedures with few risks or side effects.

Lymphocyte activation is the process by which B-cells and T-cells (types of lymphocytes) become activated to perform effector functions in an immune response. This process involves the recognition of specific antigens presented on the surface of antigen-presenting cells, such as dendritic cells or macrophages.

The activation of B-cells leads to their differentiation into plasma cells that produce antibodies, while the activation of T-cells results in the production of cytotoxic T-cells (CD8+ T-cells) that can directly kill infected cells or helper T-cells (CD4+ T-cells) that assist other immune cells.

Lymphocyte activation involves a series of intracellular signaling events, including the binding of co-stimulatory molecules and the release of cytokines, which ultimately result in the expression of genes involved in cell proliferation, differentiation, and effector functions. The activation process is tightly regulated to prevent excessive or inappropriate immune responses that can lead to autoimmunity or chronic inflammation.

Evoked potentials, motor, are a category of tests used in clinical neurophysiology to measure the electrical activity generated by the nervous system in response to a stimulus that specifically activates the motor pathways. These tests can help assess the integrity and function of the motor neurons, which are responsible for controlling voluntary muscle movements.

During a motor evoked potentials test, electrodes are placed on the scalp or directly on the surface of the brain or spinal cord. A stimulus is then applied to the motor cortex or peripheral nerves, causing the muscles to contract. The resulting electrical signals are recorded and analyzed to evaluate the conduction velocity, amplitude, and latency of the motor responses.

Motor evoked potentials tests can be useful in diagnosing various neurological conditions, such as multiple sclerosis, spinal cord injuries, and motor neuron diseases. They can also help monitor the progression of these conditions and assess the effectiveness of treatments.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Isoproterenol is a medication that belongs to a class of drugs called beta-adrenergic agonists. Medically, it is defined as a synthetic catecholamine with both alpha and beta adrenergic receptor stimulating properties. It is primarily used as a bronchodilator to treat conditions such as asthma and chronic obstructive pulmonary disease (COPD) by relaxing the smooth muscles in the airways, thereby improving breathing.

Isoproterenol can also be used in the treatment of bradycardia (abnormally slow heart rate), cardiac arrest, and heart blocks by increasing the heart rate and contractility. However, due to its non-selective beta-agonist activity, it may cause various side effects such as tremors, palpitations, and increased blood pressure. Its use is now limited due to the availability of more selective and safer medications.

Cyclic adenosine monophosphate (cAMP) is a key secondary messenger in many biological processes, including the regulation of metabolism, gene expression, and cellular excitability. It is synthesized from adenosine triphosphate (ATP) by the enzyme adenylyl cyclase and is degraded by the enzyme phosphodiesterase.

In the body, cAMP plays a crucial role in mediating the effects of hormones and neurotransmitters on target cells. For example, when a hormone binds to its receptor on the surface of a cell, it can activate a G protein, which in turn activates adenylyl cyclase to produce cAMP. The increased levels of cAMP then activate various effector proteins, such as protein kinases, which go on to regulate various cellular processes.

Overall, the regulation of cAMP levels is critical for maintaining proper cellular function and homeostasis, and abnormalities in cAMP signaling have been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.

Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.

Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.

A reflex is an automatic, involuntary and rapid response to a stimulus that occurs without conscious intention. In the context of physiology and neurology, it's a basic mechanism that involves the transmission of nerve impulses between neurons, resulting in a muscle contraction or glandular secretion.

Reflexes are important for maintaining homeostasis, protecting the body from harm, and coordinating movements. They can be tested clinically to assess the integrity of the nervous system, such as the knee-j jerk reflex, which tests the function of the L3-L4 spinal nerve roots and the sensitivity of the stretch reflex arc.

Atropine is an anticholinergic drug that blocks the action of the neurotransmitter acetylcholine in the central and peripheral nervous system. It is derived from the belladonna alkaloids, which are found in plants such as deadly nightshade (Atropa belladonna), Jimson weed (Datura stramonium), and Duboisia spp.

In clinical medicine, atropine is used to reduce secretions, increase heart rate, and dilate the pupils. It is often used before surgery to dry up secretions in the mouth, throat, and lungs, and to reduce salivation during the procedure. Atropine is also used to treat certain types of nerve agent and pesticide poisoning, as well as to manage bradycardia (slow heart rate) and hypotension (low blood pressure) caused by beta-blockers or calcium channel blockers.

Atropine can have several side effects, including dry mouth, blurred vision, dizziness, confusion, and difficulty urinating. In high doses, it can cause delirium, hallucinations, and seizures. Atropine should be used with caution in patients with glaucoma, prostatic hypertrophy, or other conditions that may be exacerbated by its anticholinergic effects.

Norepinephrine, also known as noradrenaline, is a neurotransmitter and a hormone that is primarily produced in the adrenal glands and is released into the bloodstream in response to stress or physical activity. It plays a crucial role in the "fight-or-flight" response by preparing the body for action through increasing heart rate, blood pressure, respiratory rate, and glucose availability.

As a neurotransmitter, norepinephrine is involved in regulating various functions of the nervous system, including attention, perception, motivation, and arousal. It also plays a role in modulating pain perception and responding to stressful or emotional situations.

In medical settings, norepinephrine is used as a vasopressor medication to treat hypotension (low blood pressure) that can occur during septic shock, anesthesia, or other critical illnesses. It works by constricting blood vessels and increasing heart rate, which helps to improve blood pressure and perfusion of vital organs.

Synaptic transmission is the process by which a neuron communicates with another cell, such as another neuron or a muscle cell, across a junction called a synapse. It involves the release of neurotransmitters from the presynaptic terminal of the neuron, which then cross the synaptic cleft and bind to receptors on the postsynaptic cell, leading to changes in the electrical or chemical properties of the target cell. This process is critical for the transmission of signals within the nervous system and for controlling various physiological functions in the body.

Electromyography (EMG) is a medical diagnostic procedure that measures the electrical activity of skeletal muscles during contraction and at rest. It involves inserting a thin needle electrode into the muscle to record the electrical signals generated by the muscle fibers. These signals are then displayed on an oscilloscope and may be heard through a speaker.

EMG can help diagnose various neuromuscular disorders, such as muscle weakness, numbness, or pain, and can distinguish between muscle and nerve disorders. It is often used in conjunction with other diagnostic tests, such as nerve conduction studies, to provide a comprehensive evaluation of the nervous system.

EMG is typically performed by a neurologist or a physiatrist, and the procedure may cause some discomfort or pain, although this is usually minimal. The results of an EMG can help guide treatment decisions and monitor the progression of neuromuscular conditions over time.

The motor cortex is a region in the frontal lobe of the brain that is responsible for controlling voluntary movements. It is involved in planning, initiating, and executing movements of the limbs, body, and face. The motor cortex contains neurons called Betz cells, which have large cell bodies and are responsible for transmitting signals to the spinal cord to activate muscles. Damage to the motor cortex can result in various movement disorders such as hemiplegia or paralysis on one side of the body.

The subthalamic nucleus (STN) is a small, lens-shaped structure located in the basal ganglia of the brain. It plays a crucial role in motor control and has been identified as a key target for deep brain stimulation surgery in the treatment of Parkinson's disease and other movement disorders.

The STN is involved in the regulation of movement, balance, and posture, and helps to filter and coordinate signals that are sent from the cerebral cortex to the thalamus and then on to the motor neurons in the brainstem and spinal cord. In Parkinson's disease, abnormal activity in the STN can contribute to symptoms such as tremors, rigidity, and difficulty initiating movements.

Deep brain stimulation of the STN involves implanting electrodes into the nucleus and delivering electrical impulses that help to regulate its activity. This can lead to significant improvements in motor function and quality of life for some people with Parkinson's disease.

Afferent pathways, also known as sensory pathways, refer to the neural connections that transmit sensory information from the peripheral nervous system to the central nervous system (CNS), specifically to the brain and spinal cord. These pathways are responsible for carrying various types of sensory information, such as touch, temperature, pain, pressure, vibration, hearing, vision, and taste, to the CNS for processing and interpretation.

The afferent pathways begin with sensory receptors located throughout the body, which detect changes in the environment and convert them into electrical signals. These signals are then transmitted via afferent neurons, also known as sensory neurons, to the spinal cord or brainstem. Within the CNS, the information is further processed and integrated with other neural inputs before being relayed to higher cognitive centers for conscious awareness and response.

Understanding the anatomy and physiology of afferent pathways is essential for diagnosing and treating various neurological conditions that affect sensory function, such as neuropathies, spinal cord injuries, and brain disorders.

Electrophysiology is a branch of medicine that deals with the electrical activities of the body, particularly the heart. In a medical context, electrophysiology studies (EPS) are performed to assess abnormal heart rhythms (arrhythmias) and to evaluate the effectiveness of certain treatments, such as medication or pacemakers.

During an EPS, electrode catheters are inserted into the heart through blood vessels in the groin or neck. These catheters can record the electrical activity of the heart and stimulate it to help identify the source of the arrhythmia. The information gathered during the study can help doctors determine the best course of treatment for each patient.

In addition to cardiac electrophysiology, there are also other subspecialties within electrophysiology, such as neuromuscular electrophysiology, which deals with the electrical activity of the nervous system and muscles.

The sympathetic nervous system (SNS) is a part of the autonomic nervous system that operates largely below the level of consciousness, and it functions to produce appropriate physiological responses to perceived danger. It's often associated with the "fight or flight" response. The SNS uses nerve impulses to stimulate target organs, causing them to speed up (e.g., increased heart rate), prepare for action, or otherwise respond to stressful situations.

The sympathetic nervous system is activated due to stressful emotional or physical situations and it prepares the body for immediate actions. It dilates the pupils, increases heart rate and blood pressure, accelerates breathing, and slows down digestion. The primary neurotransmitter involved in this system is norepinephrine (also known as noradrenaline).

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Neural inhibition is a process in the nervous system that decreases or prevents the activity of neurons (nerve cells) in order to regulate and control communication within the nervous system. It is a fundamental mechanism that allows for the balance of excitation and inhibition necessary for normal neural function. Inhibitory neurotransmitters, such as GABA (gamma-aminobutyric acid) and glycine, are released from the presynaptic neuron and bind to receptors on the postsynaptic neuron, reducing its likelihood of firing an action potential. This results in a decrease in neural activity and can have various effects depending on the specific neurons and brain regions involved. Neural inhibition is crucial for many functions including motor control, sensory processing, attention, memory, and emotional regulation.

'Self-stimulation' is more commonly known as "autoeroticism" or "masturbation." It refers to the act of stimulating one's own genitals for sexual pleasure, which can lead to orgasm. This behavior is considered a normal part of human sexuality and is a safe way to explore one's body and sexual responses. Self-stimulation can also be used as a means of relieving sexual tension and promoting relaxation. It is important to note that self-stimulation should always be a consensual, private activity and not performed in public or against the will of another individual.

'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

I believe there might be a misunderstanding in your question. "Dogs" is not a medical term or condition. It is the common name for a domesticated carnivore of the family Canidae, specifically the genus Canis, which includes wolves, foxes, and other extant and extinct species of mammals. Dogs are often kept as pets and companions, and they have been bred in a wide variety of forms and sizes for different purposes, such as hunting, herding, guarding, assisting police and military forces, and providing companionship and emotional support.

If you meant to ask about a specific medical condition or term related to dogs, please provide more context so I can give you an accurate answer.

Afferent neurons, also known as sensory neurons, are a type of nerve cell that conducts impulses or signals from peripheral receptors towards the central nervous system (CNS), which includes the brain and spinal cord. These neurons are responsible for transmitting sensory information such as touch, temperature, pain, sound, and light to the CNS for processing and interpretation. Afferent neurons have specialized receptor endings that detect changes in the environment and convert them into electrical signals, which are then transmitted to the CNS via synapses with other neurons. Once the signals reach the CNS, they are processed and integrated with other information to produce a response or reaction to the stimulus.

Enzyme inhibitors are substances that bind to an enzyme and decrease its activity, preventing it from catalyzing a chemical reaction in the body. They can work by several mechanisms, including blocking the active site where the substrate binds, or binding to another site on the enzyme to change its shape and prevent substrate binding. Enzyme inhibitors are often used as drugs to treat various medical conditions, such as high blood pressure, abnormal heart rhythms, and bacterial infections. They can also be found naturally in some foods and plants, and can be used in research to understand enzyme function and regulation.

Skeletal muscle, also known as striated or voluntary muscle, is a type of muscle that is attached to bones by tendons or aponeuroses and functions to produce movements and support the posture of the body. It is composed of long, multinucleated fibers that are arranged in parallel bundles and are characterized by alternating light and dark bands, giving them a striped appearance under a microscope. Skeletal muscle is under voluntary control, meaning that it is consciously activated through signals from the nervous system. It is responsible for activities such as walking, running, jumping, and lifting objects.

An electrode is a medical device that can conduct electrical currents and is used to transmit or receive electrical signals, often in the context of medical procedures or treatments. In a medical setting, electrodes may be used for a variety of purposes, such as:

1. Recording electrical activity in the body: Electrodes can be attached to the skin or inserted into body tissues to measure electrical signals produced by the heart, brain, muscles, or nerves. This information can be used to diagnose medical conditions, monitor the effectiveness of treatments, or guide medical procedures.
2. Stimulating nerve or muscle activity: Electrodes can be used to deliver electrical impulses to nerves or muscles, which can help to restore function or alleviate symptoms in people with certain medical conditions. For example, electrodes may be used to stimulate the nerves that control bladder function in people with spinal cord injuries, or to stimulate muscles in people with muscle weakness or paralysis.
3. Administering treatments: Electrodes can also be used to deliver therapeutic treatments, such as transcranial magnetic stimulation (TMS) for depression or deep brain stimulation (DBS) for movement disorders like Parkinson's disease. In these procedures, electrodes are implanted in specific areas of the brain and connected to a device that generates electrical impulses, which can help to regulate abnormal brain activity and improve symptoms.

Overall, electrodes play an important role in many medical procedures and treatments, allowing healthcare professionals to diagnose and treat a wide range of conditions that affect the body's electrical systems.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

Somatosensory evoked potentials (SEPs) are electrical signals generated in the brain and spinal cord in response to the stimulation of peripheral nerves. These responses are recorded and measured to assess the functioning of the somatosensory system, which is responsible for processing sensations such as touch, temperature, vibration, and proprioception (the sense of the position and movement of body parts).

SEPs are typically elicited by applying electrical stimuli to peripheral nerves in the arms or legs. The resulting neural responses are then recorded using electrodes placed on the scalp or other locations on the body. These recordings can provide valuable information about the integrity and function of the nervous system, and are often used in clinical settings to diagnose and monitor conditions such as nerve damage, spinal cord injury, multiple sclerosis, and other neurological disorders.

SEPs can be further categorized based on the specific type of stimulus used and the location of the recording electrodes. For example, short-latency SEPs (SLSEPs) are those that occur within the first 50 milliseconds after stimulation, and are typically recorded from the scalp over the primary sensory cortex. These responses reflect the earliest stages of sensory processing and can be used to assess the integrity of the peripheral nerves and the ascending sensory pathways in the spinal cord.

In contrast, long-latency SEPs (LLSEPs) occur after 50 milliseconds and are typically recorded from more posterior regions of the scalp over the parietal cortex. These responses reflect later stages of sensory processing and can be used to assess higher-level cognitive functions such as attention, memory, and perception.

Overall, SEPs provide a valuable tool for clinicians and researchers seeking to understand the functioning of the somatosensory system and diagnose or monitor neurological disorders.

The spinal cord is a major part of the nervous system, extending from the brainstem and continuing down to the lower back. It is a slender, tubular bundle of nerve fibers (axons) and support cells (glial cells) that carries signals between the brain and the rest of the body. The spinal cord primarily serves as a conduit for motor information, which travels from the brain to the muscles, and sensory information, which travels from the body to the brain. It also contains neurons that can independently process and respond to information within the spinal cord without direct input from the brain.

The spinal cord is protected by the bony vertebral column (spine) and is divided into 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each segment corresponds to a specific region of the body and gives rise to pairs of spinal nerves that exit through the intervertebral foramina at each level.

The spinal cord is responsible for several vital functions, including:

1. Reflexes: Simple reflex actions, such as the withdrawal reflex when touching a hot surface, are mediated by the spinal cord without involving the brain.
2. Muscle control: The spinal cord carries motor signals from the brain to the muscles, enabling voluntary movement and muscle tone regulation.
3. Sensory perception: The spinal cord transmits sensory information, such as touch, temperature, pain, and vibration, from the body to the brain for processing and awareness.
4. Autonomic functions: The sympathetic and parasympathetic divisions of the autonomic nervous system originate in the thoracolumbar and sacral regions of the spinal cord, respectively, controlling involuntary physiological responses like heart rate, blood pressure, digestion, and respiration.

Damage to the spinal cord can result in various degrees of paralysis or loss of sensation below the level of injury, depending on the severity and location of the damage.

Motor neurons are specialized nerve cells in the brain and spinal cord that play a crucial role in controlling voluntary muscle movements. They transmit electrical signals from the brain to the muscles, enabling us to perform actions such as walking, talking, and swallowing. There are two types of motor neurons: upper motor neurons, which originate in the brain's motor cortex and travel down to the brainstem and spinal cord; and lower motor neurons, which extend from the brainstem and spinal cord to the muscles. Damage or degeneration of these motor neurons can lead to various neurological disorders, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA).

Protein Kinase C (PKC) is a family of serine-threonine kinases that play crucial roles in various cellular signaling pathways. These enzymes are activated by second messengers such as diacylglycerol (DAG) and calcium ions (Ca2+), which result from the activation of cell surface receptors like G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs).

Once activated, PKC proteins phosphorylate downstream target proteins, thereby modulating their activities. This regulation is involved in numerous cellular processes, including cell growth, differentiation, apoptosis, and membrane trafficking. There are at least 10 isoforms of PKC, classified into three subfamilies based on their second messenger requirements and structural features: conventional (cPKC; α, βI, βII, and γ), novel (nPKC; δ, ε, η, and θ), and atypical (aPKC; ζ and ι/λ). Dysregulation of PKC signaling has been implicated in several diseases, such as cancer, diabetes, and neurological disorders.

T-lymphocytes, also known as T-cells, are a type of white blood cell that plays a key role in the adaptive immune system's response to infection. They are produced in the bone marrow and mature in the thymus gland. There are several different types of T-cells, including CD4+ helper T-cells, CD8+ cytotoxic T-cells, and regulatory T-cells (Tregs).

CD4+ helper T-cells assist in activating other immune cells, such as B-lymphocytes and macrophages. They also produce cytokines, which are signaling molecules that help coordinate the immune response. CD8+ cytotoxic T-cells directly kill infected cells by releasing toxic substances. Regulatory T-cells help maintain immune tolerance and prevent autoimmune diseases by suppressing the activity of other immune cells.

T-lymphocytes are important in the immune response to viral infections, cancer, and other diseases. Dysfunction or depletion of T-cells can lead to immunodeficiency and increased susceptibility to infections. On the other hand, an overactive T-cell response can contribute to autoimmune diseases and chronic inflammation.

Adrenergic beta-agonists are a class of medications that bind to and activate beta-adrenergic receptors, which are found in various tissues throughout the body. These receptors are part of the sympathetic nervous system and mediate the effects of the neurotransmitter norepinephrine (also called noradrenaline) and the hormone epinephrine (also called adrenaline).

When beta-agonists bind to these receptors, they stimulate a range of physiological responses, including relaxation of smooth muscle in the airways, increased heart rate and contractility, and increased metabolic rate. As a result, adrenergic beta-agonists are often used to treat conditions such as asthma, chronic obstructive pulmonary disease (COPD), and bronchitis, as they can help to dilate the airways and improve breathing.

There are several different types of beta-agonists, including short-acting and long-acting formulations. Short-acting beta-agonists (SABAs) are typically used for quick relief of symptoms, while long-acting beta-agonists (LABAs) are used for more sustained symptom control. Examples of adrenergic beta-agonists include albuterol (also known as salbutamol), terbutaline, formoterol, and salmeterol.

It's worth noting that while adrenergic beta-agonists can be very effective in treating respiratory conditions, they can also have side effects, particularly if used in high doses or for prolonged periods of time. These may include tremors, anxiety, palpitations, and increased blood pressure. As with any medication, it's important to use adrenergic beta-agonists only as directed by a healthcare professional.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Spinal cord stimulation (SCS) is a medical procedure that involves the use of an implanted device to deliver electrical pulses to the spinal cord. The pulses are intended to interrupt or mask the transmission of pain signals to the brain, thereby reducing the perception of pain. SCS is typically offered as a treatment option for patients with chronic pain who have not found relief from other therapies, such as medication or surgery.

During the procedure, electrodes are placed in the epidural space of the spinal cord, and connected to a pulse generator that is implanted under the skin, usually in the abdomen or buttocks. The patient can use a remote control to adjust the intensity and location of the stimulation, allowing them to customize the therapy to their individual pain patterns.

SCS is generally considered safe, although there are some risks associated with the procedure, such as infection, bleeding, and nerve damage. It is important for patients to discuss these risks with their healthcare provider before deciding whether to undergo SCS.

Membrane potential is the electrical potential difference across a cell membrane, typically for excitable cells such as nerve and muscle cells. It is the difference in electric charge between the inside and outside of a cell, created by the selective permeability of the cell membrane to different ions. The resting membrane potential of a typical animal cell is around -70 mV, with the interior being negative relative to the exterior. This potential is generated and maintained by the active transport of ions across the membrane, primarily through the action of the sodium-potassium pump. Membrane potentials play a crucial role in many physiological processes, including the transmission of nerve impulses and the contraction of muscle cells.

Reaction time, in the context of medicine and physiology, refers to the time period between the presentation of a stimulus and the subsequent initiation of a response. This complex process involves the central nervous system, particularly the brain, which perceives the stimulus, processes it, and then sends signals to the appropriate muscles or glands to react.

There are different types of reaction times, including simple reaction time (responding to a single, expected stimulus) and choice reaction time (choosing an appropriate response from multiple possibilities). These measures can be used in clinical settings to assess various aspects of neurological function, such as cognitive processing speed, motor control, and alertness.

However, it is important to note that reaction times can be influenced by several factors, including age, fatigue, attention, and the use of certain medications or substances.

Cell division is the process by which a single eukaryotic cell (a cell with a true nucleus) divides into two identical daughter cells. This complex process involves several stages, including replication of DNA, separation of chromosomes, and division of the cytoplasm. There are two main types of cell division: mitosis and meiosis.

Mitosis is the type of cell division that results in two genetically identical daughter cells. It is a fundamental process for growth, development, and tissue repair in multicellular organisms. The stages of mitosis include prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis, which divides the cytoplasm.

Meiosis, on the other hand, is a type of cell division that occurs in the gonads (ovaries and testes) during the production of gametes (sex cells). Meiosis results in four genetically unique daughter cells, each with half the number of chromosomes as the parent cell. This process is essential for sexual reproduction and genetic diversity. The stages of meiosis include meiosis I and meiosis II, which are further divided into prophase, prometaphase, metaphase, anaphase, and telophase.

In summary, cell division is the process by which a single cell divides into two daughter cells, either through mitosis or meiosis. This process is critical for growth, development, tissue repair, and sexual reproduction in multicellular organisms.

Carbachol is a cholinergic agonist, which means it stimulates the parasympathetic nervous system by mimicking the action of acetylcholine, a neurotransmitter that is involved in transmitting signals between nerves and muscles. Carbachol binds to both muscarinic and nicotinic receptors, but its effects are more pronounced on muscarinic receptors.

Carbachol is used in medical treatments to produce miosis (pupil constriction), lower intraocular pressure, and stimulate gastrointestinal motility. It can also be used as a diagnostic tool to test for certain conditions such as Hirschsprung's disease.

Like any medication, carbachol can have side effects, including sweating, salivation, nausea, vomiting, diarrhea, bradycardia (slow heart rate), and bronchoconstriction (narrowing of the airways in the lungs). It should be used with caution and under the supervision of a healthcare professional.

Tetradecanoylphorbol acetate (TPA) is defined as a pharmacological agent that is a derivative of the phorbol ester family. It is a potent tumor promoter and activator of protein kinase C (PKC), a group of enzymes that play a role in various cellular processes such as signal transduction, proliferation, and differentiation. TPA has been widely used in research to study PKC-mediated signaling pathways and its role in cancer development and progression. It is also used in topical treatments for skin conditions such as psoriasis.

The Parasympathetic Nervous System (PNS) is the part of the autonomic nervous system that primarily controls vegetative functions during rest, relaxation, and digestion. It is responsible for the body's "rest and digest" activities including decreasing heart rate, lowering blood pressure, increasing digestive activity, and stimulating sexual arousal. The PNS utilizes acetylcholine as its primary neurotransmitter and acts in opposition to the Sympathetic Nervous System (SNS), which is responsible for the "fight or flight" response.

Acetylcholine is a neurotransmitter, a type of chemical messenger that transmits signals across a chemical synapse from one neuron (nerve cell) to another "target" neuron, muscle cell, or gland cell. It is involved in both peripheral and central nervous system functions.

In the peripheral nervous system, acetylcholine acts as a neurotransmitter at the neuromuscular junction, where it transmits signals from motor neurons to activate muscles. Acetylcholine also acts as a neurotransmitter in the autonomic nervous system, where it is involved in both the sympathetic and parasympathetic systems.

In the central nervous system, acetylcholine plays a role in learning, memory, attention, and arousal. Disruptions in cholinergic neurotransmission have been implicated in several neurological disorders, including Alzheimer's disease, Parkinson's disease, and myasthenia gravis.

Acetylcholine is synthesized from choline and acetyl-CoA by the enzyme choline acetyltransferase and is stored in vesicles at the presynaptic terminal of the neuron. When a nerve impulse arrives, the vesicles fuse with the presynaptic membrane, releasing acetylcholine into the synapse. The acetylcholine then binds to receptors on the postsynaptic membrane, triggering a response in the target cell. Acetylcholine is subsequently degraded by the enzyme acetylcholinesterase, which terminates its action and allows for signal transduction to be repeated.

Adrenergic receptors are a type of G protein-coupled receptor that binds and responds to catecholamines, such as epinephrine (adrenaline) and norepinephrine (noradrenaline). Beta adrenergic receptors (β-adrenergic receptors) are a subtype of adrenergic receptors that include three distinct subclasses: β1, β2, and β3. These receptors are widely distributed throughout the body and play important roles in various physiological functions, including cardiovascular regulation, bronchodilation, lipolysis, and glucose metabolism.

β1-adrenergic receptors are primarily located in the heart and regulate cardiac contractility, chronotropy (heart rate), and relaxation. β2-adrenergic receptors are found in various tissues, including the lungs, vascular smooth muscle, liver, and skeletal muscle. They mediate bronchodilation, vasodilation, glycogenolysis, and lipolysis. β3-adrenergic receptors are mainly expressed in adipose tissue, where they stimulate lipolysis and thermogenesis.

Agonists of β-adrenergic receptors include catecholamines like epinephrine and norepinephrine, as well as synthetic drugs such as dobutamine (a β1-selective agonist) and albuterol (a non-selective β2-agonist). Antagonists of β-adrenergic receptors are commonly used in the treatment of various conditions, including hypertension, angina pectoris, heart failure, and asthma. Examples of β-blockers include metoprolol (a β1-selective antagonist) and carvedilol (a non-selective β-blocker with additional α1-adrenergic receptor blocking activity).

A synapse is a structure in the nervous system that allows for the transmission of signals from one neuron (nerve cell) to another. It is the point where the axon terminal of one neuron meets the dendrite or cell body of another, and it is here that neurotransmitters are released and received. The synapse includes both the presynaptic and postsynaptic elements, as well as the cleft between them.

At the presynaptic side, an action potential travels down the axon and triggers the release of neurotransmitters into the synaptic cleft through exocytosis. These neurotransmitters then bind to receptors on the postsynaptic side, which can either excite or inhibit the receiving neuron. The strength of the signal between two neurons is determined by the number and efficiency of these synapses.

Synapses play a crucial role in the functioning of the nervous system, allowing for the integration and processing of information from various sources. They are also dynamic structures that can undergo changes in response to experience or injury, which has important implications for learning, memory, and recovery from neurological disorders.

Transfection is a term used in molecular biology that refers to the process of deliberately introducing foreign genetic material (DNA, RNA or artificial gene constructs) into cells. This is typically done using chemical or physical methods, such as lipofection or electroporation. Transfection is widely used in research and medical settings for various purposes, including studying gene function, producing proteins, developing gene therapies, and creating genetically modified organisms. It's important to note that transfection is different from transduction, which is the process of introducing genetic material into cells using viruses as vectors.

Lipopolysaccharides (LPS) are large molecules found in the outer membrane of Gram-negative bacteria. They consist of a hydrophilic polysaccharide called the O-antigen, a core oligosaccharide, and a lipid portion known as Lipid A. The Lipid A component is responsible for the endotoxic activity of LPS, which can trigger a powerful immune response in animals, including humans. This response can lead to symptoms such as fever, inflammation, and septic shock, especially when large amounts of LPS are introduced into the bloodstream.

Ovulation induction is a medical procedure that involves the stimulation of ovulation (the release of an egg from the ovaries) in women who have difficulties conceiving due to ovulatory disorders. This is typically achieved through the use of medications such as clomiphene citrate or gonadotropins, which promote the development and maturation of follicles in the ovaries containing eggs. The process is closely monitored through regular ultrasounds and hormone tests to ensure appropriate response and minimize the risk of complications like multiple pregnancies. Ovulation induction may be used as a standalone treatment or in conjunction with other assisted reproductive technologies (ART), such as intrauterine insemination (IUI) or in vitro fertilization (IVF).

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Neural pathways, also known as nerve tracts or fasciculi, refer to the highly organized and specialized routes through which nerve impulses travel within the nervous system. These pathways are formed by groups of neurons (nerve cells) that are connected in a series, creating a continuous communication network for electrical signals to transmit information between different regions of the brain, spinal cord, and peripheral nerves.

Neural pathways can be classified into two main types: sensory (afferent) and motor (efferent). Sensory neural pathways carry sensory information from various receptors in the body (such as those for touch, temperature, pain, and vision) to the brain for processing. Motor neural pathways, on the other hand, transmit signals from the brain to the muscles and glands, controlling movements and other effector functions.

The formation of these neural pathways is crucial for normal nervous system function, as it enables efficient communication between different parts of the body and allows for complex behaviors, cognitive processes, and adaptive responses to internal and external stimuli.

Neuronal plasticity, also known as neuroplasticity or neural plasticity, refers to the ability of the brain and nervous system to change and adapt as a result of experience, learning, injury, or disease. This can involve changes in the structure, organization, and function of neurons (nerve cells) and their connections (synapses) in the central and peripheral nervous systems.

Neuronal plasticity can take many forms, including:

* Synaptic plasticity: Changes in the strength or efficiency of synaptic connections between neurons. This can involve the formation, elimination, or modification of synapses.
* Neural circuit plasticity: Changes in the organization and connectivity of neural circuits, which are networks of interconnected neurons that process information.
* Structural plasticity: Changes in the physical structure of neurons, such as the growth or retraction of dendrites (branches that receive input from other neurons) or axons (projections that transmit signals to other neurons).
* Functional plasticity: Changes in the physiological properties of neurons, such as their excitability, responsiveness, or sensitivity to stimuli.

Neuronal plasticity is a fundamental property of the nervous system and plays a crucial role in many aspects of brain function, including learning, memory, perception, and cognition. It also contributes to the brain's ability to recover from injury or disease, such as stroke or traumatic brain injury.

Smooth muscle, also known as involuntary muscle, is a type of muscle that is controlled by the autonomic nervous system and functions without conscious effort. These muscles are found in the walls of hollow organs such as the stomach, intestines, bladder, and blood vessels, as well as in the eyes, skin, and other areas of the body.

Smooth muscle fibers are shorter and narrower than skeletal muscle fibers and do not have striations or sarcomeres, which give skeletal muscle its striped appearance. Smooth muscle is controlled by the autonomic nervous system through the release of neurotransmitters such as acetylcholine and norepinephrine, which bind to receptors on the smooth muscle cells and cause them to contract or relax.

Smooth muscle plays an important role in many physiological processes, including digestion, circulation, respiration, and elimination. It can also contribute to various medical conditions, such as hypertension, gastrointestinal disorders, and genitourinary dysfunction, when it becomes overactive or underactive.

A muscle is a soft tissue in our body that contracts to produce force and motion. It is composed mainly of specialized cells called muscle fibers, which are bound together by connective tissue. There are three types of muscles: skeletal (voluntary), smooth (involuntary), and cardiac. Skeletal muscles attach to bones and help in movement, while smooth muscles are found within the walls of organs and blood vessels, helping with functions like digestion and circulation. Cardiac muscle is the specific type that makes up the heart, allowing it to pump blood throughout the body.

The somatosensory cortex is a part of the brain located in the postcentral gyrus of the parietal lobe, which is responsible for processing sensory information from the body. It receives and integrates tactile, proprioceptive, and thermoception inputs from the skin, muscles, joints, and internal organs, allowing us to perceive and interpret touch, pressure, pain, temperature, vibration, position, and movement of our body parts. The somatosensory cortex is organized in a map-like manner, known as the sensory homunculus, where each body part is represented according to its relative sensitivity and density of innervation. This organization allows for precise localization and discrimination of tactile stimuli across the body surface.

The splanchnic nerves are a set of nerve fibers that originate from the thoracic and lumbar regions of the spinal cord and innervate various internal organs. They are responsible for carrying both sensory information, such as pain and temperature, from the organs to the brain, and motor signals, which control the function of the organs, from the brain to the organs.

There are several splanchnic nerves, including the greater, lesser, and least splanchnic nerves, as well as the lumbar splanchnic nerves. These nerves primarily innervate the autonomic nervous system, which controls the involuntary functions of the body, such as heart rate, digestion, and respiration.

The greater splanchnic nerve arises from the fifth to the ninth thoracic ganglia and passes through the diaphragm to reach the abdomen. It innervates the stomach, esophagus, liver, pancreas, and adrenal glands.

The lesser splanchnic nerve arises from the tenth and eleventh thoracic ganglia and innervates the upper part of the small intestine, the pancreas, and the adrenal glands.

The least splanchnic nerve arises from the twelfth thoracic ganglion and innervates the lower part of the small intestine and the colon.

The lumbar splanchnic nerves arise from the first three or four lumbar ganglia and innervate the lower parts of the colon, the rectum, and the reproductive organs.

Adenosine Triphosphate (ATP) is a high-energy molecule that stores and transports energy within cells. It is the main source of energy for most cellular processes, including muscle contraction, nerve impulse transmission, and protein synthesis. ATP is composed of a base (adenine), a sugar (ribose), and three phosphate groups. The bonds between these phosphate groups contain a significant amount of energy, which can be released when the bond between the second and third phosphate group is broken, resulting in the formation of adenosine diphosphate (ADP) and inorganic phosphate. This process is known as hydrolysis and can be catalyzed by various enzymes to drive a wide range of cellular functions. ATP can also be regenerated from ADP through various metabolic pathways, such as oxidative phosphorylation or substrate-level phosphorylation, allowing for the continuous supply of energy to cells.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Insulin is a hormone produced by the beta cells of the pancreatic islets, primarily in response to elevated levels of glucose in the circulating blood. It plays a crucial role in regulating blood glucose levels and facilitating the uptake and utilization of glucose by peripheral tissues, such as muscle and adipose tissue, for energy production and storage. Insulin also inhibits glucose production in the liver and promotes the storage of excess glucose as glycogen or triglycerides.

Deficiency in insulin secretion or action leads to impaired glucose regulation and can result in conditions such as diabetes mellitus, characterized by chronic hyperglycemia and associated complications. Exogenous insulin is used as a replacement therapy in individuals with diabetes to help manage their blood glucose levels and prevent long-term complications.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

Neural conduction is the process by which electrical signals, known as action potentials, are transmitted along the axon of a neuron (nerve cell) to transmit information between different parts of the nervous system. This electrical impulse is generated by the movement of ions across the neuronal membrane, and it propagates down the length of the axon until it reaches the synapse, where it can then stimulate the release of neurotransmitters to communicate with other neurons or target cells. The speed of neural conduction can vary depending on factors such as the diameter of the axon, the presence of myelin sheaths (which act as insulation and allow for faster conduction), and the temperature of the environment.

A microelectrode is a small electrode with dimensions ranging from several micrometers to a few tens of micrometers in diameter. They are used in various biomedical applications, such as neurophysiological studies, neuromodulation, and brain-computer interfaces. In these applications, microelectrodes serve to record electrical activity from individual or small groups of neurons or deliver electrical stimuli to specific neural structures with high spatial resolution.

Microelectrodes can be fabricated using various materials, including metals (e.g., tungsten, stainless steel, platinum), metal alloys, carbon fibers, and semiconductor materials like silicon. The design of microelectrodes may vary depending on the specific application, with some common types being sharpened metal wires, glass-insulated metal microwires, and silicon-based probes with multiple recording sites.

The development and use of microelectrodes have significantly contributed to our understanding of neural function in health and disease, enabling researchers and clinicians to investigate the underlying mechanisms of neurological disorders and develop novel therapies for conditions such as Parkinson's disease, epilepsy, and hearing loss.

Propranolol is a medication that belongs to a class of drugs called beta blockers. Medically, it is defined as a non-selective beta blocker, which means it blocks the effects of both epinephrine (adrenaline) and norepinephrine (noradrenaline) on the heart and other organs. These effects include reducing heart rate, contractility, and conduction velocity, leading to decreased oxygen demand by the myocardium. Propranolol is used in the management of various conditions such as hypertension, angina pectoris, arrhythmias, essential tremor, anxiety disorders, and infants with congenital heart defects. It may also be used to prevent migraines and reduce the risk of future heart attacks. As with any medication, it should be taken under the supervision of a healthcare provider due to potential side effects and contraindications.

Cytokines are a broad and diverse category of small signaling proteins that are secreted by various cells, including immune cells, in response to different stimuli. They play crucial roles in regulating the immune response, inflammation, hematopoiesis, and cellular communication.

Cytokines mediate their effects by binding to specific receptors on the surface of target cells, which triggers intracellular signaling pathways that ultimately result in changes in gene expression, cell behavior, and function. Some key functions of cytokines include:

1. Regulating the activation, differentiation, and proliferation of immune cells such as T cells, B cells, natural killer (NK) cells, and macrophages.
2. Coordinating the inflammatory response by recruiting immune cells to sites of infection or tissue damage and modulating their effector functions.
3. Regulating hematopoiesis, the process of blood cell formation in the bone marrow, by controlling the proliferation, differentiation, and survival of hematopoietic stem and progenitor cells.
4. Modulating the development and function of the nervous system, including neuroinflammation, neuroprotection, and neuroregeneration.

Cytokines can be classified into several categories based on their structure, function, or cellular origin. Some common types of cytokines include interleukins (ILs), interferons (IFNs), tumor necrosis factors (TNFs), chemokines, colony-stimulating factors (CSFs), and transforming growth factors (TGFs). Dysregulation of cytokine production and signaling has been implicated in various pathological conditions, such as autoimmune diseases, chronic inflammation, cancer, and neurodegenerative disorders.

Efferent neurons are specialized nerve cells that transmit signals from the central nervous system (CNS), which includes the brain and spinal cord, to effector organs such as muscles or glands. These signals typically result in a response or action, hence the term "efferent," derived from the Latin word "efferre" meaning "to carry away."

Efferent neurons are part of the motor pathway and can be further classified into two types:

1. Somatic efferent neurons: These neurons transmit signals to skeletal muscles, enabling voluntary movements and posture maintenance. They have their cell bodies located in the ventral horn of the spinal cord and send their axons through the ventral roots to innervate specific muscle fibers.
2. Autonomic efferent neurons: These neurons are responsible for controlling involuntary functions, such as heart rate, digestion, respiration, and pupil dilation. They have a two-neuron chain arrangement, with the preganglionic neuron having its cell body in the CNS (brainstem or spinal cord) and synapsing with the postganglionic neuron in an autonomic ganglion near the effector organ. Autonomic efferent neurons can be further divided into sympathetic, parasympathetic, and enteric subdivisions based on their functions and innervation patterns.

In summary, efferent neurons are a critical component of the nervous system, responsible for transmitting signals from the CNS to various effector organs, ultimately controlling and coordinating numerous bodily functions and responses.

A decerebrate state is a medical condition that results from severe damage to the brainstem, specifically to the midbrain and above. This type of injury can cause motor responses characterized by rigid extension of the arms and legs, with the arms rotated outward and the wrists and fingers extended. The legs are also extended and the toes pointed downward. These postures are often referred to as "decerebrate rigidity" or "posturing."

The decerebrate state is typically seen in patients who have experienced severe trauma, such as a car accident or gunshot wound, or who have suffered from a large stroke or other type of brain hemorrhage. It can also occur in some cases of severe hypoxia (lack of oxygen) to the brain, such as during cardiac arrest or drowning.

The decerebrate state is a serious medical emergency that requires immediate treatment. If left untreated, it can lead to further brain damage and even death. Treatment typically involves providing supportive care, such as mechanical ventilation to help with breathing, medications to control blood pressure and prevent seizures, and surgery to repair any underlying injuries or bleeding. In some cases, patients may require long-term rehabilitation to regain lost function and improve their quality of life.

The cerebral cortex is the outermost layer of the brain, characterized by its intricate folded structure and wrinkled appearance. It is a region of great importance as it plays a key role in higher cognitive functions such as perception, consciousness, thought, memory, language, and attention. The cerebral cortex is divided into two hemispheres, each containing four lobes: the frontal, parietal, temporal, and occipital lobes. These areas are responsible for different functions, with some regions specializing in sensory processing while others are involved in motor control or associative functions. The cerebral cortex is composed of gray matter, which contains neuronal cell bodies, and is covered by a layer of white matter that consists mainly of myelinated nerve fibers.

Adenylate cyclase is an enzyme that catalyzes the conversion of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP). It plays a crucial role in various cellular processes, including signal transduction and metabolism. Adenylate cyclase is activated by hormones and neurotransmitters that bind to G-protein-coupled receptors on the cell membrane, leading to the production of cAMP, which then acts as a second messenger to regulate various intracellular responses. There are several isoforms of adenylate cyclase, each with distinct regulatory properties and subcellular localization.

Analysis of Variance (ANOVA) is a statistical technique used to compare the means of two or more groups and determine whether there are any significant differences between them. It is a way to analyze the variance in a dataset to determine whether the variability between groups is greater than the variability within groups, which can indicate that the groups are significantly different from one another.

ANOVA is based on the concept of partitioning the total variance in a dataset into two components: variance due to differences between group means (also known as "between-group variance") and variance due to differences within each group (also known as "within-group variance"). By comparing these two sources of variance, ANOVA can help researchers determine whether any observed differences between groups are statistically significant, or whether they could have occurred by chance.

ANOVA is a widely used technique in many areas of research, including biology, psychology, engineering, and business. It is often used to compare the means of two or more experimental groups, such as a treatment group and a control group, to determine whether the treatment had a significant effect. ANOVA can also be used to compare the means of different populations or subgroups within a population, to identify any differences that may exist between them.

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine, a type of small signaling protein involved in immune response and inflammation. It is primarily produced by activated macrophages, although other cell types such as T-cells, natural killer cells, and mast cells can also produce it.

TNF-α plays a crucial role in the body's defense against infection and tissue injury by mediating inflammatory responses, activating immune cells, and inducing apoptosis (programmed cell death) in certain types of cells. It does this by binding to its receptors, TNFR1 and TNFR2, which are found on the surface of many cell types.

In addition to its role in the immune response, TNF-α has been implicated in the pathogenesis of several diseases, including autoimmune disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, as well as cancer, where it can promote tumor growth and metastasis.

Therapeutic agents that target TNF-α, such as infliximab, adalimumab, and etanercept, have been developed to treat these conditions. However, these drugs can also increase the risk of infections and other side effects, so their use must be carefully monitored.

... above 1 kHz can be beyond the range of amplification possible via acoustic stimulation. Electric stimulation (CI), on the other ... Electric acoustic stimulation (EAS) is the use of a hearing aid and a cochlear implant technology together in the same ear. EAS ... This acoustic stimulation proves to be particularly effective in the low frequencies, though a severe hearing loss (> 70 dB HL ... Gstoettner W., Helbig S., Maier N., Kiefer J., Radeloff A., Adunka O. (2006). Ipsilateral Electric Acoustic Stimulation of the ...
"Electric Acoustic Stimulation". www.medel.com. Retrieved 2022-05-13. "Vibrant Soundbridge Middle Ear Implant". www.medel.com. ... In 2005, MED-EL released their first electric acoustic stimulation system (EAS). This new type of implant combines both ... "Who is a Candidate for an Electric-Acoustic Stimulation (EAS) Cochlear Implant?". AudiologyOnline. Retrieved 2022-05-13. " ... The Bonebridge bone conduction implant was the first implant on the market to offer direct drive stimulation of the bone ...
"RMS Hydrocarbon Acoustic Stimulation System". AIC. Archived from the original on 25 June 2018. Retrieved 28 September 2018. " ... In 2003, he led the Hydrocarbon Acoustic Stimulation (RMS) development, technology which increases the efficiency of oil ...
Electric-acoustic stimulation of the auditory system. ORL 61:334-40. B. J. Gantz, C. Turner, and K. E. Gfeller, "Acoustic plus ... The concept of combining simultaneous electric-acoustic stimulation (EAS) for the purposes of better hearing was first ... The stimulation can also be done anywhere along the optic signal's pathway. The optical nerve can be stimulated in order to ... Sacral nerve stimulation for treatment of refractory urinary urge incontinence. Sacral nerve study group. J Urol 1999 Aug;16(2 ...
Hoffman HS, Fleshler M (September 1963). "Startle Reaction: Modification by Background Acoustic Stimulation". Science. 141 ( ... The stimuli are usually acoustic, but tactile stimuli (e.g. via air puffs onto the skin) and light stimuli are also used. When ... A burst of white noise is usually used as the acoustic startle stimulus. Typical durations are 20 ms for prepulse and 40 ms for ... Kumari V, Soni W, Sharma T (June 2001). "Influence of cigarette smoking on prepulse inhibition of the acoustic startle response ...
Kessler, L. W. (1970). "Ultrasonic Stimulation of Optical Scattering in Nematic Liquid Crystals". Applied Physics Letters. 17 ( ... These are the scanning acoustic microscope (SAM), confocal scanning acoustic microscope (CSAM), and C-mode scanning acoustic ... Planar acoustic images do not often use all return echoes from all depths to make the visible acoustic image. Instead, a time ... Acoustic microscopy is microscopy that employs very high or ultra high frequency ultrasound. Acoustic microscopes operate non- ...
"A primary acoustic startle circuit: lesion and stimulation studies". Journal of Neuroscience. 2 (6): 791-805. doi:10.1523/ ... The acoustic startle reflex is thought to be caused by an auditory stimulus greater than 80 decibels. The reflex is typically ... A reflex from hearing a sudden loud noise will happen in the primary acoustic startle reflex pathway consisting of three main ... The role of the BNST in the acoustic startle reflex may be attributed to specific areas within the nucleus responsible for ...
Pinette MG, Blackstone J, Wax JR, Cartin A (June 2005). "Using fetal acoustic stimulation to shorten the biophysical profile". ... Fetal heart rate Fetal breathing Fetal movement Fetal tone Amniotic fluid volume Use of vibroacoustic stimulation to accelerate ...
Fay, R. R., & Popper, A. N. (1974). Acoustic stimulation of the ear of the goldfish (Carassius auratus). Journal of ...
Hilali, S.; Whitfield, I. C. (October 1953). "Responses of the trapezoid body to acoustic stimulation with pure tones". The ... which had varying phases according to stimulation frequency. This phenomenon was interpreted as the result of a second harmonic ...
Visser, G.H.A.; Mulder, H.H.; Wit, H.P.; Mulder, E.J.H.; Prechtl, H.F.R. (1989). "Vibro-acoustic stimulation of the human fetus ... Vibroacoustic stimulation is a technique involving the repetitive stimulation of the fetus, by applying a vibroacoustic ... Stimulation trials continue into the neonatal period (first 28 days after birth) by presenting the same auditory stimulus, to ... Both auditory and vibroacoustic stimulation have been used in habituation. ...
... are sounds that are heard without any external acoustic stimulation. Endaural means "in the ear". Phenomena ...
... following acoustic stimulation. Using acoustic stimuli to activate the MOC reflex pathway, recordings have been made from ... Cody and Johnstone (1982) and Rajan and Johnstone (1988a; 1988b) showed that constant acoustic stimulation that in (which ... Acoustic stimulation of the inner hair cells sends a neural signal to the posteroventral cochlear nucleus (PVCN), and the axons ... electrical stimulation of neurons other than MOCS fibres. Therefore, electrical stimulation of the MOCS may not give an ...
"Cochlear Dead Regions Constrain the Benefit of Combining Acoustic Stimulation With Electric Stimulation". Ear and Hearing. 35 ( ...
Townsend GL, Cody DTR (1971). The averaged inion response evoked by acoustic stimulation: its relation to the saccule. Ann Otol ... Rosengren SM, Todd NPM, Colebatch JG (2005). Vestibular-evoked extraocular potentials produced by stimulation with bone- ... bone vibration and short duration electrical stimulation. It is likely that both air-conducted and bone-conducted stimuli ... Vestibulocollic reflexes evoked by short-duration galvanic stimulation in man. J Physiol 513(2):587-97. Curthoys IS, Kim J, ...
"Mapping the tonotopic organization in human auditory cortex with minimally salient acoustic stimulation". Cerebral Cortex. 22 ( ... Consistently, electro stimulation to the aSTG of this patient resulted in impaired speech perception (see also for similar ... and fMRI The latter study further demonstrated that working memory in the AVS is for the acoustic properties of spoken words ... The authors also reported that stimulation in area Spt and the inferior IPL induced interference during both object-naming and ...
A CI bypasses acoustic hearing by direct electrical stimulation of the auditory nerve. Through everyday listening and auditory ... Their design distributed stimulation using a single channel. William House also invented a cochlear implant in 1961. In 1964, ... Further research found that the electrical stimulation of the CI is at least partly responsible for the general reduction in ... This would suggest that it is the electrical stimulation that explains the decrease in tinnitus symptoms for many patients, and ...
"Mapping the tonotopic organization in human auditory cortex with minimally salient acoustic stimulation". Cerebral Cortex. 22 ( ... Studies in mature A1 have focused on neuromodulatory influences and have found that direct and indirect vagus nerve stimulation ... Barton B, Venezia JH, Saberi K, Hickok G, Brewer AA (December 2012). "Orthogonal acoustic dimensions define auditory field maps ... which altered the ability of the auditory cortex to plastically reorganize after changes in the acoustic environment, thereby ...
Outer hair cells serve as acoustic amplifiers for stimulation of the inner hair cells. Outer hair cells respond primarily to ... A metronome was used as part of a technique to test the effects of musical and rhythmic stimulation in physical rehabilitation ... eds.). Cochlear Blood Flow Changes With Short Sound Stimulation. pp. 95-109. ISBN 9783131026811. OCLC 33361359. {{cite book ...
This physical stimulation appears to enhance the cell-repair effects of the inflammatory response. The first large scale ... This is based on the acoustic radiation force which causes particles to be attracted to either the nodes or anti-nodes of the ... Acoustic tweezers is an emerging tool for contactless separation, concentration and manipulation of microparticles and ... Long-duration therapeutic ultrasound called sustained acoustic medicine is a daily slow-release therapy that can be applied to ...
Familiarity tends to play a large role in the amount of positive stimulation observed. For example, a man listening to a ... Saccular acoustic sensitivity is considered to be simply an extension of the sense of hearing through the use of the saccule. ... Saccular acoustic sensitivity is a measurement of the ear's affectability to sound. The saccule's normal function is to keep ... Saccular acoustic sensitivity has a variety of physiological as well as mental/emotional effects. Perhaps the most observable ...
The main hypothesized function of the acoustic reflex is the protection of the organ of Corti against excessive stimulation ( ... no matter which ear was exposed to the loud sound stimulation. The prevalence of bilateral acoustic reflexes in persons 18-30 ... the sound used to trigger the acoustic reflex). For most animals, the acoustic reflex is the contraction of both middle ear ... The acoustic reflex threshold (ART) is the sound pressure level (SPL) from which a sound stimulus with a given frequency will ...
Chouard, CH; Meyer, B; Josset, P; Buche, JF (1983). "The effect of the acoustic nerve chronic electric stimulation upon the ... The study showed that selective electrical stimulation of eight to twelve electrodes, each isolated from the others, placed in ... House, WF; Urban, J (1973). "Long term results of electrode implantation and electronic stimulation of the cochlea in man". Ann ... Djourno, A; Eyries, C (August 1957). "[Auditory prosthesis by means of a distant electrical stimulation of the sensory nerve ...
... a comparison of fetal acoustic stimulation with acid-base determinations". Am J Obstet Gynecol. 155 (4): 726-728. doi:10.1016/ ... Vibroacoustic stimulation can wake the fetus, and is sometimes used to speed up the test or to facilitate further evaluation of ...
The Long Range Acoustic Device (LRAD) is an acoustic hailing device developed by LRAD Corporation to send messages and warning ... PERSONNEL HALTING and STIMULATION RESPONSE (PHaSR) Fact Sheet, Air Force Research Laboratory, Office of Public Affairs, April ... "Long Range Acoustic Device Industry Applications - Public Safety & Security Solution". Archived from the original on 2017-03-10 ... Long range acoustic device mounted on police vehicle, 2004 Republican National Convention, New York City Swedish police in riot ...
Electric Acoustic Stimulation in Children W: Van de Heyning P, Kleine Punte A (eds): Cochlear Implants and Hearing Preservation ...
Shockwave therapy uses acoustic sound waves to alter tissue mechanics and inflammation. Lastly, personalized exercise plans ... Therapeutic ultrasound provides deep tissue thermal stimulation to increase range of motion and tendon strength and is often ... This therapy refers to when stimulation occurs via light and reportedly increases energy and antioxidant production. Hyperbaric ...
Due to this mechanism, for example, incoming acoustic stimuli can be processed with astonishing speed as when comprehending ... how automatic predictions about upcoming auditory events can be generated on the basis of regular environmental stimulation. ...
Phonemic Restoration with Simulations of Cochlear Implants and Combined Electric-Acoustic Stimulation". Journal of the ... It is believed that humans and other vertebrates have evolved the ability to complete acoustic signals that are critical but ... For people with cochlear implants, acoustic simulations of the implant indicated the importance of spectral resolution. When ... "Dynamic cortical representations of perceptual fulling-in for missing acoustic rhythm". Scientific Reports. 7 (1): 17536. doi: ...
Phonemic Restoration with Simulations of Cochlear Implants and Combined Electric-Acoustic Stimulation". Journal of the ... "The discrimination of voice cues in simulations of bimodal electro-acoustic cochlear-implant hearing". The Journal of the ... "The Cochlear Implant EEG Artifact Recorded From an Artificial Brain for Complex Acoustic Stimuli". IEEE Transactions on Neural ...
... above 1 kHz can be beyond the range of amplification possible via acoustic stimulation. Electric stimulation (CI), on the other ... Electric acoustic stimulation (EAS) is the use of a hearing aid and a cochlear implant technology together in the same ear. EAS ... This acoustic stimulation proves to be particularly effective in the low frequencies, though a severe hearing loss (> 70 dB HL ... Gstoettner W., Helbig S., Maier N., Kiefer J., Radeloff A., Adunka O. (2006). Ipsilateral Electric Acoustic Stimulation of the ...
Functional Brain Network Changes Following Use of an Allostatic, Closed ‐Loop, Acoustic Stimulation Neurotechnology for ...
... Effect of contralateral acoustic stimulation on cochlear tuning measured using stimulus frequency and distortion product OAEs ... Effect of contralateral acoustic stimulation on cochlear tuning measured using stimulus frequency and distortion product OAEs ... Boothalingam, Sriram and Lineton, Ben (2012) Effect of contralateral acoustic stimulation on cochlear tuning measured using ...
Acoustic Stimulation Improves Postconcussive Symptoms News 22/11/23 By Elana Gotkine HealthDay Reporter ... 22, 2023 (HealthDay News) -- Ten hours of acoustic stimulation improves postconcussive symptoms, but linking tones to brain ... listening to acoustic stimulation based on ones own brain electrical activity reduces symptoms, or improves brain function or ... heart rate variability, more than randomly generated, computer engineered acoustic stimulation," the authors write. ...
Acoustic stimulation. Johnson and Elliott performed a randomized, blinded trial on 23 subjects to compare acoustic stimulation ... 38] Of those who received acoustic stimulation, 12 of 12 fetuses shifted to a spine-lateral position after acoustic stimulation ... Fetal acoustic stimulation, an adjunct to external cephalic version: a blinded, randomized crossover study. Am J Obstet Gynecol ... 23] Adjuncts such as tocolysis, regional anesthesia, and acoustic stimulation when appropriate may improve ECV success rates. ...
Dynamic Stimulation is combines acoustic and vibrational therapy to ensure deep relaxation. ... The Binaural Acoustic & Dynamic Stimulation is a computer-controlled acoustic and vibrational therapy that trains the brain to ...
T1 - Response properties of neurons in the inferior colliculus of the monaurally deafened ferret to acoustic stimulation of the ... Response properties of neurons in the inferior colliculus of the monaurally deafened ferret to acoustic stimulation of the ... Response properties of neurons in the inferior colliculus of the monaurally deafened ferret to acoustic stimulation of the ... Response properties of neurons in the inferior colliculus of the monaurally deafened ferret to acoustic stimulation of the ...
keywords = "Amplification, Cochlear implants, Electric and acoustic stimulation (EAS), Frequency compression, Hearing aids", ... on speech recognition in candidates for combined Electric and Acoustic Stimulation (EAS). In: Journal of Speech, Language, and ... on speech recognition in candidates for combined Electric and Acoustic Stimulation (EAS). Journal of Speech, Language, and ... on speech recognition in candidates for combined Electric and Acoustic Stimulation (EAS), Journal of Speech, Language, and ...
audiologycochlear implanthearingelectric-acoustic stimulationEASmappingfrequency-to-placemismatchspeechrecognitionfilter ... Influence of electric mismatches on electric-acoustic stimulation outcomes (Dillon et al., 2023). ... Influence of electric frequency-to-place mismatches on the early speech recognition outcomes for electric-acoustic stimulation ... For both groups, the unaided thresholds determined the acoustic cutoff frequency (i.e., > 65 dB HL). For default maps, the ...
... electric acoustic stimulation systems, middle ear implant system, bone conduction implant system, and bone conduction hearing ... Our cochlear implant systems, electric acoustic systems, middle ear implant system and bone conduction systems have restored ...
Enhancement of Sleep Quality and Stability Using Acoustic Stimulation During Slow Wave Sleep ...
Audio and visual stimulation reduces abdominal discomfort associated with flexible sigmoidoscopy. This effect appears to be due ... audio stimulation alone, or audio and visual stimulation. Patient discomfort ratings and affect states were measured prior to ... Audio and visual stimulation reduces patient discomfort during screening flexible sigmoidoscopy Am J Gastroenterol. 1998 Jul;93 ... Acoustic Stimulation* * Affect / physiology * Aged * Anger / physiology * Anxiety / prevention & control * Arousal / physiology ...
... and electric acoustic stimulation. ...
Acoustic Stimulation * Animals * Auditory Perception / physiology* * Biological Evolution * Cerebral Cortex* / anatomy & ... Rather than resulting from differences in elementary acoustic properties, this activity seems to reflect higher order auditory ...
Drilling & Stimulation Properties. Continuous Wave Technique (CWT) for Acoustic Measurements on Small Samples. ... as a method for measuring the acoustic velocities on small core samples, including in particular shale drill cuttings. The CWT ...
Stable-foamed HCl-based acid system providing enhanced diversion properties for acid stimulations enabling better treatment ...
... was used for acoustic stimulation in order to contrast SL and MML. Acoustic stimulation was conducted in a randomized order for ... Acoustic Stimulation. Seven different modified noise stimuli were created in MATLAB (Matlab R2015a; Mathworks, Natick, MA, USA ... Acoustic Stimulation. Prima facie, the stimulus IBP40 appeared to produce the strongest tinnitus suppression regardless of ... In order to test for a potential bias due to the sequence of the stimuli used for acoustic stimulation (position effect), a ...
Successful first installation of taml level 5 Flexrite multilateral completion system designed for branch stimulation in North ... Stimulation of a multilateral well during the construction phase is possible but can add additional days to a drilling rig ... Offline stimulation can be performed more economically after well completion using a dedicated vessel; however, well operations ... The expected load cases during stimulation prevented the use of a Swellpacker® system seal due to induced tensile loading. A ...
Coordinated reset (CR) stimulation is a theory-based stimulation technique that was designed to specifically counteract ... Coordinated reset (CR) stimulation is a theory-based stimulation technique that was designed to specifically counteract ... In particular, for clinically relevant parameter ranges double-random CR stimulation, i.e. CR stimulation with the specific ... stimulation-induced long-lasting desynchronization effects should favorably be robust to variations of the stimulation ...
Twenty-two government-sponsored stimulation trea... * Gas Content Determinations of Salt Samples Using Acoustic Responses ... Effects of Stimulation Treatments on Coalbeds and Surrounding Strata: Evidence from Underground Observations ... This Bureau of Mines report examines the coal mine roof damage potential of stimulation treatments. ...
1982) A primary acoustic startle circuit: lesion and stimulation studies. J Neurosci 2:791-805. ... Acoustic stimuli were produced by a Pacer 8 Ω speaker placed within the sound-insulated chamber at a distance of 10 cm from the ... The acoustic startle reflex is a short-latency motor response to a loud and unexpected noise. The reflex involves the rapid and ... 1994b) Lesions of the central gray block the sensitization of the acoustic startle response in rats. Brain Res 661:163-173. ...
Mechanical stimulation may play a role in regulation of inflammation. In vitro studies demonstrated that both pulsed ... Similarly to ESWT, the mechanical stimulation obtained using PEMFs may play a role for treatment of tendinopathy and for tendon ... Similarly to ESWT, the mechanical stimulation obtained using PEMFs may play a role for treatment of tendinopathy and for tendon ... In this manuscript the rational of mechanical stimulations and the clinical studies on the efficacy of extracorporeal shock ...
Lacking a stimulation artifact and having a higher degree of spatial specificity, infrared neural stimulation (INS) has the ... ES, however, is subject to off-target stimulation and stimulation artifacts disguising the true functionality of the specific ... surgeons commonly use electrical stimulation (ES) during intraoperative nerve monitoring (IONM) to assess a nerves functional ... Kaylie, D. M., Gilbert, E., Horgan, M. A., Delashaw, J. B. & McMenomey, S. O. Acoustic Neuroma Surgery Outcomes. Otol Neurotol ...
The GAINSWave uses acoustic waves to vibrate the plaque loose. The waves also do slight damage to the penile tissue. This ... tissue stimulation doesnt hurt. The cavitation causes your body to recruit healing factors from your blood to repair the ...
T cell stimulation assay. Approximately 2×10e5 PBMC were stimulated with 1 ug of each of the SARS-CoV-2 peptide pools (15-mer ... Samples were acquired on the Attune NxT acoustic focusing cytometer (Life Technologies). Data were analyzed using FlowJo v10 ( ... J) Secreted IFNγ levels following ex vivo PBMC stimulation with either SARS-CoV-s peptide pools or anti-CD3 in seronegative, ... Monocyte stimulation assay. Approximately 1×10e6 PBMC were cultured in the presence of RPMI (controls), bacterial and viral ...
Asymmetric Hearing Loss , Challenging Surgical Cases , Cognition , Bimodal, Bilateral, & Electric-Acoustic Stimulation ...
Somatosensory Event-related Potentials from Orofacial Skin Stretch Stimulation The JoVE video player is compatible with HTML5 ...
Acoustic Neural Stimulation. This relatively new treatment has shown to be effective in reducing, and in some cases eliminating ... This vagus nerve stimulation, coupled with the sound-based stimulation of the auditory cortex, can "turn down" the patients ... An uncommon but serious cause is an acoustic neuroma, a noncancerous (benign) tumor of part of the nerve leading from the inner ...
Ansel BM, Kent RD: Acoustic-phonetic contrasts and intelligibility in the dysarthria associated with mixed cerebral palsy. J ... Vercueil L, Pollak P, Fraix V, Caputo E, Moro E, Benazzouz A, et al: Deep brain stimulation in the treatment of severe dystonia ... Stimulation and Coagulation of the Posteromedial Hypothalamus for Intractable Pain, with Reference to β-Endorphins Applied ... Koy A, Hellmich M, Pauls KA, Marks W, Lin JP, Fricke O, Timmermann L: Effects of deep brain stimulation in dyskinetic cerebral ...
  • We have a variety of hearing solutions to cater to different types and degrees of hearing loss i.e., cochlear implant systems, electric acoustic stimulation systems, middle ear implant system, bone conduction implant system, and bone conduction hearing system. (medel.com)
  • In binaurally intact animals, tonal stimulation of the contralateral ear evoked excitatory activity at the majority (94%) of recording loci, whereas stimulation of the ipsilateral ear evoked activity at only 33% of recording loci. (edu.au)
  • In acutely ablated animals, the majority of contralateral (90%) and ipsilateral (70%) loci were excited by tonal stimulation of the intact ear. (edu.au)
  • Following monaural acoustic stimulation, increased activity of the contralateral auditory cortex could be demonstrated in 9 subjects. (thieme-connect.com)
  • The results of the monaural acoustic stimulation show clearly the predominant signal increase of contralateral areas in the primary auditory cortex. (thieme-connect.com)
  • Lacking a stimulation artifact and having a higher degree of spatial specificity, infrared neural stimulation (INS) has the potential to improve upon clinical ES for IONM. (nature.com)
  • Acoustic Neural Stimulation. (banishtinnitus.net)
  • WEDNESDAY, Nov. 22, 2023 (HealthDay News) -- Ten hours of acoustic stimulation improves postconcussive symptoms, but linking tones to brain electrical activity does not reduce symptoms more than random tones, according to a study published online Nov. 22 in the Annals of Clinical and Translational Neurology . (msdmanuals.com)
  • We study the long-lasting effects of CR stimulation with randomized stimulus amplitudes and/or randomized stimulus timing in networks of leaky integrate-and-fire (LIF) neurons with spike-timing-dependent plasticity. (frontiersin.org)
  • CR stimulation with the specific combination of stimulus amplitude randomization and stimulus time randomization, may outperform regular CR stimulation with respect to long-lasting desynchronization. (frontiersin.org)
  • In addition, our results provide the first evidence that an effective reduction of the overall stimulation current by stimulus amplitude randomization may improve the frequency robustness of long-lasting therapeutic effects of brain stimulation. (frontiersin.org)
  • An alternating current (AC) voltage that mirrors the waveform of the acoustic stimulus at low-moderate levels of stimulation. (audiologyonline.com)
  • Tonotopie organization of the auditory cortex was visualized using stimulation by pulsed sine tones of 500 Hz and 4000 Hz. (thieme-connect.com)
  • First, intra-amygdala infusions of the CCK B receptor agonist pentagastrin (0, 0.01, 0.1, 1, and 10 n m ) produced a dose-related potentiation of acoustic startle responses. (jneurosci.org)
  • These results show that amygdala CCK B receptor-mediated mechanisms are involved in the potentiation of acoustic startle responses. (jneurosci.org)
  • Hyperekplexia (HE), first described by Kirstein and Silfverskiold in 1958, is a rare and nonepileptic clinical entity characterized by exaggerated and generalized startle responses to acoustic, optic, or tactile stimuli [ 1 ]. (hindawi.com)
  • The results of this study do not suggest that in a primarily active duty group with postconcussive symptoms, listening to acoustic stimulation based on one's own brain electrical activity reduces symptoms, or improves brain function or heart rate variability, more than randomly generated, computer engineered acoustic stimulation," the authors write. (msdmanuals.com)
  • The Binaural Acoustic & Dynamic Stimulation is a computer-controlled acoustic and vibrational therapy that trains the brain to relax and benefit from deep relaxation techniques. (4elementswellnesscenter.com)
  • Chronic high-frequency deep brain stimulation (HF DBS) is the standard of care for medically refractory PD. (frontiersin.org)
  • Data about outcome of deep brain stimulation (DBS) in these patients remains scarce. (karger.com)
  • I also think it's having an effect on the general population - you might want to read Allan Freys papers on microwave hearing, he highlighted the stimulation of dopamines in the brain - when we talk addiction, it really is addiction - addiction centers of the brain. (mast-victims.org)
  • For both groups, the unaided thresholds determined the acoustic cutoff frequency (i.e. (figshare.com)
  • The study included only children with hearing thresholds below or equal to 15 dB, type A tympanometry, and presence of acoustic reflexes. (scielo.br)
  • In this manuscript the rational of mechanical stimulations and the clinical studies on the efficacy of extracorporeal shock wave (ESW) and PEMF will be discussed. (frontiersin.org)
  • Sensorineural hearing loss has different treatment options depending on its severity, including cochlear implants, middle ear implants, and electric acoustic stimulation. (medel.com)
  • Electric stimulation (CI), on the other hand, is capable of providing high-frequency information up to 8 kHz. (wikipedia.org)
  • Purpose: To compare the effects of conventional amplification (CA) and digital frequency compression (DFC) amplification on the speech recognition abilities of candidates for a partial-insertion cochlear implant, that is, candidates for combined electric and acoustic stimulation (EAS). (elsevierpure.com)
  • Influence of electric frequency-to-place mismatches on the early speech recognition outcomes for electric-acoustic stimulation users. (figshare.com)
  • Past research already stressed the impact of noise stimulation as well as the superiority of amplitude modulated (AM) pure tones at the individual tinnitus frequency for RI in tonal tinnitus. (karger.com)
  • As PD symptoms are associated with different pathological synchronous rhythms, stimulation-induced long-lasting desynchronization effects should favorably be robust to variations of the stimulation frequency. (frontiersin.org)
  • Varying the CR stimulation frequency (with respect to the frequency of abnormal target rhythm) and the number of separately stimulated neuronal subpopulations, we reveal parameter regions and related mechanisms where the two qualitatively different randomization mechanisms improve the robustness of long-lasting desynchronization effects of CR. (frontiersin.org)
  • IE uses a low-amplitude, high-frequency source (often a spring-loaded or solenoid-driven ball bearing) to obtain a frequency-domain measure of the compression wave's travel time between the outer surface and internal planar discontinuities or external boundaries that exhibit an acoustic impedance mismatch. (cdc.gov)
  • The main problem in hyperekplexia is the incomplete development of inhibitory mechanisms or exaggerated stimulation of excitatory mediators. (hindawi.com)
  • 70 dB HL) above 1 kHz can be beyond the range of amplification possible via acoustic stimulation. (wikipedia.org)
  • YUN Training With Pelvic Floor Magnetic Stimulation Efficacy Is this combination strategy an effective option for the treatment of female stress urinary incontinence and sexual function? (medscape.com)
  • Microenergy Acoustic Pulses Restore Pelvic Floor Muscles Could this non-invasive therapy prove to be an effective therapeutic option for pelvic floor disorders? (medscape.com)
  • Removing a miner from beneath the hazard requires not only measurements of remote (noncontact) responses, but also remote vibration stimulation. (cdc.gov)
  • Tinnitus is not a disease, but rather a symptom of an underlying condition such as age related hearing loss, exposure to loud noise, Meniere's disease, acoustic neuroma, circulatory system disorder, or TMJ disorder. (aadsm.org)
  • The study contributes to the bridging of the gap between subjective perceptions and objective measurements, providing valuable insights for acoustic design considerations. (bvsalud.org)
  • The feasibility of delineating damaged structures through the combination of remote stimulation and remote (noncontact) response measurements is the focus of this investigation. (cdc.gov)
  • IONM seeks to preserve peripheral nerve function through electrical stimulation (ES) of at risk nerves throughout surgery and examining any changes in the amplitude and latency of the evoked signals that are indicative of damage. (nature.com)
  • Symptoms may effectively be suppressed by HF DBS, but return shortly after cessation of stimulation. (frontiersin.org)
  • Schizophrenia patients show deficits in prepulse inhibition (PPI) of the acoustic startle reflex (ASR), an operational measure of the information-processing abnormalities that may underlie the cognitive and positive symptoms of the disease. (unige.ch)
  • The Band Became Known as the Acoustic Vibration Appreciation Society, or A.V.A.S. Since his Graduation from college in 1999, Andy has traveled the World with these different music groups, playing Festivals in US, England, Scotland, and Jamaica. (deepdiscount.com)
  • A total of 37 patients undergoing routine screening flexible sigmoidoscopy were randomized to receive no intervention, audio stimulation alone, or audio and visual stimulation. (nih.gov)
  • Coordinated reset (CR) stimulation is a theory-based stimulation technique that was designed to specifically counteract neuronal synchrony by desynchronization. (frontiersin.org)
  • Electric acoustic stimulation (EAS) is the use of a hearing aid and a cochlear implant technology together in the same ear. (wikipedia.org)
  • Electric stimulation of the auditory system via cochlear implant is a commonly used technique for individuals with a severe to profound sensorineural hearing loss, as well as for those adults and children with some residual hearing. (wikipedia.org)
  • The concept of combining simultaneous electric-acoustic stimulation (EAS) for the purposes of better hearing was first described by C. von Ilberg and J. Kiefer, from the Universitätsklinik Frankfurt, Germany, in 1999. (wikipedia.org)
  • Important factors for preserving residual hearing are: Special atraumatic soft electrodes Smallest possible acoustic trauma due to cochleostomy drilling Smallest possible mechanical trauma due to drilling and electrode insertion Avoidance of inflammatory and fibrotic reactions (contamination with blood, bone dust, middle ear bacteria, etc. (wikipedia.org)
  • Cochlear implant (CI) recipients with hearing preservation experience significant improvements in speech recognition with electric-acoustic stimulation (EAS) as compared to with a CI alone, although outcomes across EAS users vary. (figshare.com)
  • Cochlear implant prostheses are designed to create hearing sensation by direct electrical stimulation of auditory neurons (nerves). (hoagiesgifted.org)
  • The inner ear then processes the acoustic and electric stimuli simultaneously, to give the patient the perception of sound. (wikipedia.org)
  • Dette paradigme indeholder en mekanisme til at identificere både påvisning af, og forskelsbehandling, som adskiller sig akustiske og elektriske stimuli ved hjælp af hjerte-rate som et resultat foranstaltning. (jove.com)
  • DAS data contain critical information about the fracture geometry as linearly relatable induced strain variations during the stimulation. (onepetro.org)
  • These data show that unilateral cochlear removal in adult ferrets leads to a rapid and dramatic increase in the proportion of neurons in the ICC ipsilateral to the intact ear that is excited by acoustic stimulation of that ear. (edu.au)
  • The original single-channel implants have been replaced by greater use of multichannel implants, where the stimulation is distributed across an array of electrodes that evoke a wider range of auditory perception. (hoagiesgifted.org)
  • Influence of electric mismatches on electric-acoustic stimulation outcomes (Dillon et al. (figshare.com)
  • The aim of this study was to determine whether audio and visual stimulation reduces discomfort during flexible sigmoidoscopy and whether the effects of the stimulation are secondary to distraction. (nih.gov)
  • Audio and visual stimulation reduces abdominal discomfort associated with flexible sigmoidoscopy. (nih.gov)
  • The phenomenon of short-term tinnitus suppression by different forms of acoustic stimulation is referred to as residual inhibition (RI). (karger.com)
  • However, no clear evidence of a clinical value of ESW and PEMF has been found in literature with regards to the treatment of tendinopathy in human, so further clinical trials are needed to confirm the promising hypotheses concerning the effectiveness of ESWT and PEMF mechanical stimulation. (frontiersin.org)
  • Mechanical stimulation may play a role in regulation of inflammation. (frontiersin.org)
  • Similarly to ESWT, the mechanical stimulation obtained using PEMFs may play a role for treatment of tendinopathy and for tendon regeneration, increasing in vitro TGF-β production, as well as scleraxis and collagen I gene expression. (frontiersin.org)
  • In this manuscript, we will analyze the rationale of mechanical stimulation by Extracorporeal shock wave (ESW) and Pulsed electromagnetic fields (PEMF) for tendon regeneration, and its possible role in the treatment of different tendinopathies. (frontiersin.org)
  • They received binaural, monaural right, and monaural left stimulation with pulsed sine tones of 1000 Hz at a pulse rate of 6 Hz and a sound pressure level of 100 dB SPL. (thieme-connect.com)
  • The completion design must be robust enough to withstand any planned stimulation activities. (halliburton.com)
  • The acoustic startle reflex is a sensitive index of "anxiety" and "fear. (jneurosci.org)
  • To meet these complex requirements, Halliburton developed the 7 5/8-inch FlexRite junction system in 2019 with a smaller host casing size that enables deeper junction placement in wells where contingency drilling liners might be required as well as sufficient pressure ratings for branch stimulation. (halliburton.com)
  • Furthermore, the high levels of stimulation that were used in some of these animal experiments were not typical of realistic exposure situations. (cdc.gov)
  • Parasympathetic stimulation prompts high flow with a low glycoprotein content, and sympathetic activity prompts a low flow rate and saliva that is more viscous because of increased protein and glycoprotein content. (medscape.com)
  • The speech processor is worn externally and converts characteristics of sound signals (acoustic parameters) into electrical characteristics (parameters). (hoagiesgifted.org)
  • The purpose of the device is to improve speech recognition of cochlear implant users by representing acoustic (sound) information. (hoagiesgifted.org)
  • As demonstrated by multilateral stimulation case histories within carbonate formations, hydraulic integrity of a junction is essential for optimal stimulation results. (halliburton.com)
  • Distributed acoustic sensing (DAS) has recently gained importance in monitoring hydraulic fracturing treatments in the oil and gas industry. (onepetro.org)
  • Participants performed Giordani's "Caro mio ben" aria in five venues, and the acoustic parameters reverberance (T30 and EDT), clarity (C80), early vocal support (STv), and tonal color (EDTf) were measured. (bvsalud.org)
  • These percepts correlated significantly with objective acoustic parameters traditionally linked to vocal support, reverberation, and timbre. (bvsalud.org)
  • Significantly better effects were observed for the subgroup with noise-like tinnitus ( n = 14), especially directly after stimulation offset. (karger.com)
  • Computational studies on CR stimulation of plastic neuronal networks revealed long-lasting desynchronization effects obtained by down-regulating abnormal synaptic connectivity. (frontiersin.org)
  • In chronically ablated animals, 80-90% of loci were excited by ipsilateral stimulation. (edu.au)
  • The external acoustic meatus (external auditory canal) is formed by cartilage and bone (temporal). (medscape.com)
  • 2011, a clinical syndrome involving No data are yet available to predict stimulation (Figure). (cdc.gov)
  • In surgical procedures where the risk of accidental nerve damage is prevalent, surgeons commonly use electrical stimulation (ES) during intraoperative nerve monitoring (IONM) to assess a nerve's functional integrity. (nature.com)
  • Rather than resulting from differences in elementary acoustic properties, this activity seems to reflect higher order auditory processing. (nih.gov)
  • Tinnitus is the perception of sound in the absence of external acoustic stimulation. (aadsm.org)
  • The auricle and external acoustic meatus (or external auditory canal) compose the external ear. (medscape.com)
  • The mandibular condyle sits anterior to the bony portion of the external acoustic meatus (external auditory canal). (medscape.com)
  • Stimulation of a multilateral well during the construction phase is possible but can add additional days to a drilling rig schedule. (halliburton.com)
  • Furthermore, the probability of interneurones to fire with low interspike intervals during 80 Hz auditory stimulation was reduced in Df(h15q13)/+ mice, an effect that was partially reversed by the Kv3.1 channel modulator, RE1. (lu.se)