Cochlea: 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.Hair Cells, Auditory: 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.Organ of Corti: The spiral EPITHELIUM containing sensory AUDITORY HAIR CELLS and supporting cells in the cochlea. Organ of Corti, situated on the BASILAR MEMBRANE and overlaid by a gelatinous TECTORIAL MEMBRANE, converts sound-induced mechanical waves to neural impulses to the brain.Spiral Ganglion: The sensory ganglion of the COCHLEAR NERVE. The cells of the spiral ganglion send fibers peripherally to the cochlear hair cells and centrally to the COCHLEAR NUCLEI of the BRAIN STEM.Cochlear Diseases: Pathological processes of the snail-like structure (COCHLEA) of the inner ear (LABYRINTH) which can involve its nervous tissue, blood vessels, or fluid (ENDOLYMPH).Hair Cells, Auditory, Inner: Auditory sensory cells of organ of Corti, usually placed in one row medially to the core of spongy bone (the modiolus). Inner hair cells are in fewer numbers than the OUTER AUDITORY HAIR CELLS, and their STEREOCILIA are approximately twice as thick as those of the outer hair cells.Hair Cells, Auditory, Outer: 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.Spiral Ligament of Cochlea: A spiral thickening of the fibrous lining of the cochlear wall. Spiral ligament secures the membranous COCHLEAR DUCT to the bony spiral canal of the COCHLEA. Its spiral ligament fibrocytes function in conjunction with the STRIA VASCULARIS to mediate cochlear ion homeostasis.Hearing: The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.Ear, Inner: The essential part of the hearing organ consists of two labyrinthine compartments: the bony labyrinthine and the membranous labyrinth. The bony labyrinth is a complex of three interconnecting cavities or spaces (COCHLEA; VESTIBULAR LABYRINTH; and SEMICIRCULAR CANALS) in the TEMPORAL BONE. Within the bony labyrinth lies the membranous labyrinth which is a complex of sacs and tubules (COCHLEAR DUCT; SACCULE AND UTRICLE; and SEMICIRCULAR DUCTS) forming a continuous space enclosed by EPITHELIUM and connective tissue. These spaces are filled with LABYRINTHINE FLUIDS of various compositions.Labyrinth Supporting Cells: Cells forming a framework supporting the sensory AUDITORY HAIR CELLS in the organ of Corti. Lateral to the medial inner hair cells, there are inner pillar cells, outer pillar cells, Deiters cells, Hensens cells, Claudius cells, Boettchers cells, and others.Evoked Potentials, Auditory, Brain Stem: 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.Stria Vascularis: A layer of stratified EPITHELIUM forming the endolymphatic border of the cochlear duct at the lateral wall of the cochlea. Stria vascularis contains primarily three cell types (marginal, intermediate, and basal), and capillaries. The marginal cells directly facing the ENDOLYMPH are important in producing ion gradients and endochoclear potential.Cochlear Nerve: 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.Round Window, Ear: Fenestra of the cochlea, an opening in the basal wall between the MIDDLE EAR and the INNER EAR, leading to the cochlea. It is closed by a secondary tympanic membrane.Cochlear Microphonic Potentials: The electric response of the cochlear hair cells to acoustic stimulation.Deafness: A general term for the complete loss of the ability to hear from both ears.Perilymph: The fluid separating the membranous labyrinth from the osseous labyrinth of the ear. It is entirely separate from the ENDOLYMPH which is contained in the membranous labyrinth. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1396, 642)Endolymph: The lymph fluid found in the membranous labyrinth of the ear. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Stapes: One of the three ossicles of the middle ear. It transmits sound vibrations from the INCUS to the internal ear (Ear, Internal see LABYRINTH).Otoacoustic Emissions, Spontaneous: 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.Tectorial Membrane: A membrane, attached to the bony SPIRAL LAMINA, overlying and coupling with the hair cells of the ORGAN OF CORTI in the inner ear. It is a glycoprotein-rich keratin-like layer containing fibrils embedded in a dense amorphous substance.Scala Tympani: The lower chamber of the COCHLEA, extending from the round window to the helicotrema (the opening at the apex that connects the PERILYMPH-filled spaces of scala tympani and SCALA VESTIBULI).Hearing Loss: A general term for the complete or partial loss of the ability to hear from one or both ears.Hearing Loss, Noise-Induced: Hearing loss due to exposure to explosive loud noise or chronic exposure to sound level greater than 85 dB. The hearing loss is often in the frequency range 4000-6000 hertz.Cochlear Duct: A spiral tube that is firmly suspended in the bony shell-shaped part of the cochlea. This ENDOLYMPH-filled cochlear duct begins at the vestibule and makes 2.5 turns around a core of spongy bone (the modiolus) thus dividing the PERILYMPH-filled spiral canal into two channels, the SCALA VESTIBULI and the SCALA TYMPANI.Auditory Threshold: The audibility limit of discriminating sound intensity and pitch.Temporal Bone: Either of a pair of compound bones forming the lateral (left and right) surfaces and base of the skull which contains the organs of hearing. It is a large bone formed by the fusion of parts: the squamous (the flattened anterior-superior part), the tympanic (the curved anterior-inferior part), the mastoid (the irregular posterior portion), and the petrous (the part at the base of the skull).Chinchilla: A genus of the family Chinchillidae which consists of three species: C. brevicaudata, C. lanigera, and C. villidera. They are used extensively in biomedical research.Acoustic Stimulation: Use of sound to elicit a response in the nervous system.Hearing Loss, Sensorineural: Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.Nerve Regeneration: Renewal or physiological repair of damaged nerve tissue.Growth Cones: Bulbous enlargement of the growing tip of nerve axons and dendrites. They are crucial to neuronal development because of their pathfinding ability and their role in synaptogenesis.Gerbillinae: A subfamily of the Muridae consisting of several genera including Gerbillus, Rhombomys, Tatera, Meriones, and Psammomys.Guinea Pigs: 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.Cochlear Implantation: 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.Neurons: 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.Vestibulocochlear Nerve: The 8th cranial nerve. The vestibulocochlear nerve has a cochlear part (COCHLEAR NERVE) which is concerned with hearing and a vestibular part (VESTIBULAR NERVE) which mediates the sense of balance and head position. The fibers of the cochlear nerve originate from neurons of the SPIRAL GANGLION and project to the cochlear nuclei (COCHLEAR NUCLEUS). The fibers of the vestibular nerve arise from neurons of Scarpa's ganglion and project to the VESTIBULAR NUCLEI.Noise: Any sound which is unwanted or interferes with HEARING other sounds.Tympanic Membrane: 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.Neurons, Efferent: Neurons which send impulses peripherally to activate muscles or secretory cells.Cochlear Implants: 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.Auditory Pathways: 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.Decapodiformes: A superorder of CEPHALOPODS comprised of squid, cuttlefish, and their relatives. Their distinguishing feature is the modification of their fourth pair of arms into tentacles, resulting in 10 limbs.Ear, Middle: The space and structures directly internal to the TYMPANIC MEMBRANE and external to the inner ear (LABYRINTH). Its major components include the AUDITORY OSSICLES and the EUSTACHIAN TUBE that connects the cavity of middle ear (tympanic cavity) to the upper part of the throat.Nerve Tissue ProteinsEar Canal: The narrow passage way that conducts the sound collected by the EAR AURICLE to the TYMPANIC MEMBRANE.Presbycusis: Gradual bilateral hearing loss associated with aging that is due to progressive degeneration of cochlear structures and central auditory pathways. Hearing loss usually begins with the high frequencies then progresses to sounds of middle and low frequencies.Axonal Transport: The directed transport of ORGANELLES and molecules along nerve cell AXONS. Transport can be anterograde (from the cell body) or retrograde (toward the cell body). (Alberts et al., Molecular Biology of the Cell, 3d ed, pG3)Labyrinthine Fluids: Fluids found within the osseous labyrinth (PERILYMPH) and the membranous labyrinth (ENDOLYMPH) of the inner ear. (From Gray's Anatomy, 30th American ed, p1328, 1332)Animals, Newborn: Refers to animals in the period of time just after birth.Efferent Pathways: 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.Cochlear Nucleus: 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.Vestibule, Labyrinth: An oval, bony chamber of the inner ear, part of the bony labyrinth. It is continuous with bony COCHLEA anteriorly, and SEMICIRCULAR CANALS posteriorly. The vestibule contains two communicating sacs (utricle and saccule) of the balancing apparatus. The oval window on its lateral wall is occupied by the base of the STAPES of the MIDDLE EAR.Motor Neurons: Neurons which activate MUSCLE CELLS.Evoked Potentials, Auditory: The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.Sound: A type of non-ionizing radiation in which energy is transmitted through solid, liquid, or gas as compression waves. Sound (acoustic or sonic) radiation with frequencies above the audible range is classified as ultrasonic. Sound radiation below the audible range is classified as infrasonic.Endolymphatic Hydrops: An accumulation of ENDOLYMPH in the inner ear (LABYRINTH) leading to buildup of pressure and distortion of intralabyrinthine structures, such as COCHLEA and SEMICIRCULAR CANALS. It is characterized by SENSORINEURAL HEARING LOSS; TINNITUS; and sometimes VERTIGO.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Gene Expression Regulation, Developmental: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.Neurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.Myelin Sheath: The lipid-rich sheath surrounding AXONS in both the CENTRAL NERVOUS SYSTEMS and PERIPHERAL NERVOUS SYSTEM. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (SCHWANN CELLS in the peripheral and OLIGODENDROGLIA in the central nervous system). Deterioration of the sheath in DEMYELINATING DISEASES is a serious clinical problem.Optic Nerve: The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Petrous Bone: The dense rock-like part of temporal bone that contains the INNER EAR. Petrous bone is located at the base of the skull. Sometimes it is combined with the MASTOID PROCESS and called petromastoid part of temporal bone.Otologic Surgical Procedures: Surgery performed on the external, middle, or internal ear.Ear Ossicles: A mobile chain of three small bones (INCUS; MALLEUS; STAPES) in the TYMPANIC CAVITY between the TYMPANIC MEMBRANE and the oval window on the wall of INNER EAR. Sound waves are converted to vibration by the tympanic membrane then transmitted via these ear ossicles to the inner ear.Labyrinth Diseases: Pathological processes of the inner ear (LABYRINTH) which contains the essential apparatus of hearing (COCHLEA) and balance (SEMICIRCULAR CANALS).Synapses: 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.Sensory Receptor Cells: Specialized afferent neurons capable of transducing sensory stimuli into NERVE IMPULSES to be transmitted to the CENTRAL NERVOUS SYSTEM. Sometimes sensory receptors for external stimuli are called exteroceptors; for internal stimuli are called interoceptors and proprioceptors.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Retinal Ganglion Cells: Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.Mechanotransduction, Cellular: The process by which cells convert mechanical stimuli into a chemical response. It can occur in both cells specialized for sensing mechanical cues such as MECHANORECEPTORS, and in parenchymal cells whose primary function is not mechanosensory.Mice, Inbred CBAElectric Stimulation: Use of electric potential or currents to elicit biological responses.Nerve Growth Factors: Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.Vibration: A continuing periodic change in displacement with respect to a fixed reference. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Neurites: In tissue culture, hairlike projections of neurons stimulated by growth factors and other molecules. These projections may go on to form a branched tree of dendrites or a single axon or they may be reabsorbed at a later stage of development. "Neurite" may refer to any filamentous or pointed outgrowth of an embryonal or tissue-culture neural cell.Acoustics: The branch of physics that deals with sound and sound waves. In medicine it is often applied in procedures in speech and hearing studies. With regard to the environment, it refers to the characteristics of a room, auditorium, theatre, building, etc. that determines the audibility or fidelity of sounds in it. (From Random House Unabridged Dictionary, 2d ed)Hearing Disorders: Conditions that impair the transmission of auditory impulses and information from the level of the ear to the temporal cortices, including the sensorineural pathways.Cats: 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)Ear: The hearing and equilibrium system of the body. It consists of three parts: the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR. Sound waves are transmitted through this organ where vibration is transduced to nerve signals that pass through the ACOUSTIC NERVE to the CENTRAL NERVOUS SYSTEM. The inner ear also contains the vestibular organ that maintains equilibrium by transducing signals to the VESTIBULAR NERVE.Vestibulocochlear Nerve Diseases: Pathological processes of the VESTIBULOCOCHLEAR NERVE, including the branches of COCHLEAR NERVE and VESTIBULAR NERVE. Common examples are VESTIBULAR NEURITIS, cochlear neuritis, and ACOUSTIC NEUROMA. Clinical signs are varying degree of HEARING LOSS; VERTIGO; and TINNITUS.Meniere Disease: A disease of the inner ear (LABYRINTH) that is characterized by fluctuating SENSORINEURAL HEARING LOSS; TINNITUS; episodic VERTIGO; and aural fullness. It is the most common form of endolymphatic hydrops.Dendrites: Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.Schwann Cells: Neuroglial cells of the peripheral nervous system which form the insulating myelin sheaths of peripheral axons.Saccule and Utricle: Two membranous sacs within the vestibular labyrinth of the INNER EAR. The saccule communicates with COCHLEAR DUCT through the ductus reuniens, and communicates with utricle through the utriculosaccular duct from which the ENDOLYMPHATIC DUCT arises. The utricle and saccule have sensory areas (acoustic maculae) which are innervated by the VESTIBULAR NERVE.Olivary Nucleus: 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.Optic Chiasm: The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.Mice, Inbred C57BLAudiometry: 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.Interferometry: Measurement of distances or movements by means of the phenomena caused by the interference of two rays of light (optical interferometry) or of sound (acoustic interferometry).Audiometry, Pure-Tone: Measurement of hearing based on the use of pure tones of various frequencies and intensities as auditory stimuli.Nerve Degeneration: Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.Neural Conduction: The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.Anatomy, Regional: The anatomical study of specific regions or parts of organisms, emphasizing the relationship between the various structures (e.g. muscles, nerves, skeletal, cardiovascular, etc.).Time Factors: Elements of limited time intervals, contributing to particular results or situations.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Mice, Knockout: 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.Kanamycin: Antibiotic complex produced by Streptomyces kanamyceticus from Japanese soil. Comprises 3 components: kanamycin A, the major component, and kanamycins B and C, the minor components.Inferior Colliculi: The posterior pair of the quadrigeminal bodies which contain centers for auditory function.Semaphorins: A family of proteins that mediate axonal guidance. Semaphorins act as repulsive cues for neuronal GROWTH CONES and bind to receptors on their filopodia. At least 20 different molecules have been described and divided into eight classes based on domain organization and species of origin. Classes 1 and 2 are invertebrate, classes 3-7 are vertebrate, and class V are viral. Semaphorins may be secreted (classes 2, 3, and V), transmembrane (classes 1, 4, 5, and 6), or membrane-anchored (class 7). All semaphorins possess a common 500-amino acid extracellular domain which is critical for receptor binding and specificity, and is also found in plexins and scatter factor receptors. Their C termini are class-specific and may contain additional sequence motifs.Wallerian Degeneration: Degeneration of distal aspects of a nerve axon following injury to the cell body or proximal portion of the axon. The process is characterized by fragmentation of the axon and its MYELIN SHEATH.Electrophysiology: 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.Rats, Sprague-Dawley: 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.Semaphorin-3A: The prototypical and most well-studied member of the semaphorin family. Semaphorin-3A is an axon-repulsive guidance cue for migrating neurons in the developing nervous system. It has so far been found only in vertebrates, and binds to NEUROPILIN-1/plexin complex receptors on growth cones. Like other class 3 semaphorins, it is a secreted protein.Membrane Potentials: 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).Chick Embryo: The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.Hearing Tests: Part of an ear examination that measures the ability of sound to reach the brain.Endolymphatic Sac: The blind pouch at the end of the endolymphatic duct. It is a storage reservoir for excess ENDOLYMPH, formed by the blood vessels in the membranous labyrinth.Neurotrophin 3: A neurotrophic factor involved in regulating the survival of visceral and proprioceptive sensory neurons. It is closely homologous to nerve growth factor beta and BRAIN-DERIVED NEUROTROPHIC FACTOR.Signal Transduction: 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.Central Nervous System: The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.Vestibular Nerve: The vestibular part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). The vestibular nerve fibers arise from neurons of Scarpa's ganglion and project peripherally to vestibular hair cells and centrally to the VESTIBULAR NUCLEI of the BRAIN STEM. These fibers mediate the sense of balance and head position.Cells, Cultured: 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.Ganglia, Spinal: Sensory ganglia located on the dorsal spinal roots within the vertebral column. The spinal ganglion cells are pseudounipolar. The single primary branch bifurcates sending a peripheral process to carry sensory information from the periphery and a central branch which relays that information to the spinal cord or brain.Stereocilia: Mechanosensing organelles of hair cells which respond to fluid motion or fluid pressure changes. They have various functions in many different animals, but are primarily used in hearing.Tinnitus: A nonspecific symptom of hearing disorder characterized by the sensation of buzzing, ringing, clicking, pulsations, and other noises in the ear. Objective tinnitus refers to noises generated from within the ear or adjacent structures that can be heard by other individuals. The term subjective tinnitus is used when the sound is audible only to the affected individual. Tinnitus may occur as a manifestation of COCHLEAR DISEASES; VESTIBULOCOCHLEAR NERVE DISEASES; INTRACRANIAL HYPERTENSION; CRANIOCEREBRAL TRAUMA; and other conditions.Afferent Pathways: Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.Peripheral Nerves: The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
The human cochlea contains on the order of 3,500 inner hair cells and 12,000 outer hair cells at birth. The outer hair cells ... Efferent synapses occur on outer hair cells and on afferent axons under inner hair cells. The presynaptic terminal bouton is ... In mammals, the auditory hair cells are located within the spiral organ of Corti on the thin basilar membrane in the cochlea of ... Housley, G D; Ashmore, J F (1992). "Ionic currents of outer hair cells isolated from the guinea-pig cochlea". The Journal of ...
The vestibulocochlear anastomosis carries the efferent axons into the cochlea, where they innervate the organ of Corti (OC). ... The shell axons often cover 1-2 octaves of tonotopic length. Their terminal arbor is quite sparse, however. All currently known ... Intrinsic LOCS derived axons travel only approximately 1 µm within the organ of Corti, generally spiraling apically. They give ... The Cochlea. New York: Springer. pp. 435-502. ISBN 978-0-387-94449-4. OCLC 33243443. Warr, WB.; Beck, JE.; Neely, ST. (1997). " ...
The axons of the auditory nerve originate from the hair cells of the cochlea in the inner ear. Different sound frequencies are ...
The cochlea is tonotopically mapped in a spiral fashion, with lower frequencies localizing at the apex of the cochlea, and high ... They stimulate the peripheral axons of the primary auditory neurons, which then send information to the brain via the auditory ... Heredity: factors like early aging of the cochlea and susceptibility of the cochlea for drug insults are genetically determined ... Strial/metabolic: characterised by atrophy of stria vascularis in all turns of cochlea. Located in the lateral wall of the ...
... named for the spiral shape it shares with the cochlea. These central axons exit the cochlea at its base and form a nerve trunk ... The axons from the low-frequency region of the cochlea project to the ventral portion of the dorsal cochlear nucleus and the ... The peripheral axons of auditory nerve fibers form synaptic connections with the hair cells of the cochlea via ribbon synapses ... "peripheral axon" and the "central axon", respectively. The peripheral process is sometimes referred to as a dendrite, although ...
The axons of these cells make up the auditory nerve, encoding the rectified stimulus. The auditory nerve responses select ... As the organ of hearing, the cochlea consists of two membranes, Reissner's and the basilar membrane. The basilar membrane moves ... the signal is broken up into different frequencies that are naturally selected by the cochlea and hair cells. Because of the ...
Neurons whose cell bodies lie in the spiral ganglion are strung along the bony core of the cochlea, and send fibers (axons) ... The cell bodies of the spiral ganglion neurons are found in the modiolus, the conical shaped central axis in the cochlea. ... Their dendrites make synaptic contact with the base of hair cells, and their axons are bundled together to form the auditory ... Diagrammatic longitudinal section of the cochlea Organ of corti This article incorporates text in the public domain from the ...
The axons from the higher frequency organ of corti hair cells project to the dorsal portion of the ventral cochlear nucleus and ... Information is brought to the nuclei from the ipsilateral cochlea via the cochlear nerve. Several tasks are performed in the ... Axons from the spiral ganglion cells of the lower frequencies innervate the ventrolateral portions of the ventral cochlear ... Each fiber is an axon of a spiral ganglion cell that represents a particular frequency of sound, and a particular range of ...
Rémy Pujol, Régis Nouvian, Marc Lenoir, "Hair cells (cochlea.eu) *^ Ashmore, Jonathan Felix (1987). "A fast motile response in ... Efferent synapses occur on outer hair cells and on afferent axons under inner hair cells. The presynaptic terminal bouton is ... The outer hair cells mechanically amplify low-level sound that enters the cochlea.[6][7] The amplification may be powered by ... Cross-section of the cochlea. The inner hair cells are located at the termination of the "inner hair cell nerves" and the outer ...
... or vibration-sensitive neurons in the cochlea of the ear. The axons of sensory receptor cells travel into the spinal cord or ... Axons transmit signals to other neurons by means of specialized junctions called synapses. A single axon may make as many as ... Once a neuron is in place, it extends dendrites and an axon into the area around it. Axons, because they commonly extend a ... its axon, equally magnified, would become a cable a few centimeters in diameter, extending more than a kilometer. These axons ...
An acidophyllic mucopolysaccharide-containing substance was discovered, especially in cochleas, maculas, and crista ampullaris ... of patients with DFNA9 (a chromosome locus), as well as severe degeneration of vestibular and cochlear sensory axons and ...
The axons of most of the CNIC cells form the brachium of IC and leave the brainstem to travel to the ipsilateral thalamus. ... The result of having input from both cochleas is an increase in the firing rate of the MSO units. The neurons in the MSO are ... The axons of both cell types leave the AVCN as large tract called the ventral acoustic stria, which forms part of the trapezoid ... The axons from the MSO continue to higher parts of the pathway via the ipsilateral lateral lemniscus tract.(Yost, 2000) The ...
The nucleus geniculatus medialis receives axons from auditory axons. From the cochlea, peripheral auditory information goes to ... VO receives its pallidal afferent axons from the medial pallidum. The trajectory of pallidal afferent axons is complex. Axons ... The thalamocortical axons of the VPC send their axons to the primary somatosensory area (areas 3b and 1) where there is also a ... From there, the axons cross the internal capsule as the comb system. Axons arrives at the lateral border of the subthalamic ...
They originate in the apical end of the cochlea and they are located near fibers that transmit low frequency sounds in the ... sensitive fibers are found to be simple bipolar cells in the auditory ganglion with a diameter of 1.6-2.2 µm at the axon and ... Complete surgical removal of the entire cochlea, lagena, and calumellae completely abolishes any response to infrasound. This ...
Since the ipsilateral axons enter the nucleus laminaris dorsally while the contralateral axons enter ventrally, sounds from ... Jeffress' model proposes that two signals even from an asynchronous arrival of sound in the cochlea of each ear will converge ... Due to differing lengths and a finite conduction speed within the axons of the delay lines, different coincidence detector ...
He identified the cells' axon, which he called an "axis cylinder", and its dendrites, which he referred to as protoplasmic ... structures that are associated with outer hair cells in the cochlea of the inner ear. Deiters died in 1863 from typhoid fever ...
... growing axons compete for limiting amounts of target-derived trophic factors and axons that fail to receive sufficient trophic ... In the developing auditory system, developing cochlea generate bursts of activity which spreads across the inner hair cells and ... Once axons reach their target areas, activity-dependent mechanisms come into play. Although synapse formation is an activity- ... Many neurons migrating along the anterior-posterior axis of the body use existing axon tracts to migrate along; this is called ...
In axons, similar effects can be seen. There is swelling in mitochondria and other membrane bound organelles. There is also a ... Loss of sensory receptors in the cochlea, vestibules, and retina result in ganglion degeneration and transneuronal degeneration ... Transneuronal degeneration affects dendrites and axons as well. There is evident shrinkage in the main dendritic shafts. The ... transneuronal degeneration causes the hyperphosphorylation of the tau protein and redistributing those proteins from the axon ...
... which then sends the energy through the oval window and into the cochlea where it is changed into a chemical signal by hair ... neurons in the superior olive which accept innervation from each ear with different connecting axon lengths. Some cells are ...
... nerve auscultation autonomic autonomic ganglion axial skeleton axial view axilla axillary artery axis axon axon collateral axon ... cochlea) Tectorial membrane of atlanto-axial joint tectospinal tract tectum tegmen tympani tegmentum tela choroidae ... claustrum clava clavicle climbing fiber clinoid clitoris clivus cloaca clonus coccyx cochlea cochlear duct cochlear nerve ... fastigial nucleus fastigium fat fauces femoral artery femoral neck femoral triangle femur fenestra fenestra cochleae fenestra ...
The vibrations travel through the bones of the inner ear to the cochlea. In the cochlea, the vibrations are transduced into ... Axons must be able to communicate with each other to ensure that ones with the same positional tags innervate the same area of ... Higher frequency sounds are at the base of the cochlea, if it were unrolled, and low frequency sounds are at the apex. This ... Sensory neurons extend a single unbranched axon to the olfactory bulb such that the projections from neurons expressing a ...
At the cochlea base the Basilar is at its narrowest and most stiff (high-frequencies), at the cochlea apex it is at its widest ... Some of these axons come from the cochlear nucleus and cross over to the other side before traveling on to the superior olivary ... The inner ear consists of the cochlea and several non-auditory structures. The cochlea has three fluid-filled sections, and ... Efferent projections from the brain to the cochlea also play a role in the perception of sound, although this is not well ...
The axons of these single tactile receptors will converge into a single nerve trunk, and the signal is then sent to the spinal ... This opening allows the vibrations to move through the liquid in the cochlea where the receptive organ is able to sense it. ... When a louder sound is heard, more hair cells are stimulated and the intensity of firing of axons in the cochlear nerve is ... The ossicles which are connected to the eardrum pass the vibrations to the fluid-filled cochlea. Once the vibrations reach the ...
Axon growth from the subgenual organ in grasshoppers is contingent on semaphorin I. In the honeybee Apis mellifera, the sensing ... A cochlea-like displacement threshold and a direct response to sound". Journal of Neurobiology. 25 (9): 1167-1185. doi:10.1002/ ... J. T. Wong, W. T. Yu & T. P. O'Connor (September 1997). "Transmembrane grasshopper Semaphorin I promotes axon outgrowth in vivo ... with the actual sensitivity being comparable to the cochlea. In cockroaches Blaberus discoidalis and Blattella germanica, the ...
Those whose axons project out of the aVCN through the trapezoid body, T stellate cells, have longer dendrites than bushy cells ... Fibers that carry information from the apex of the cochlea that are tuned to low frequencies contact neurons in the ventral ... Globular bushy cells project large axons to the contralateral medial nucleus of the trapezoid body (MNTB), in the superior ... 1991). "Projections of physiologically characterized globular bushy cell axons from the cochlear nucleus of the cat." J Comp ...
স্নায়ু অক্ষ (Axon). *স্নায়ুপ্রশাখা (Dendrite). *স্নায়ুসন্নিধি (Synapse). *স্নায়ুধারীয় বর্জ্য নিষ্কাশন ব্যবস্থা (Glymphatic ...
A non-autonomous function of the core PCP protein VANGL2 directs peripheral axon turning in the developing cochlea ... A non-autonomous function of the core PCP protein VANGL2 directs peripheral axon turning in the developing cochlea ... A non-autonomous function of the core PCP protein VANGL2 directs peripheral axon turning in the developing cochlea ... A non-autonomous function of the core PCP protein VANGL2 directs peripheral axon turning in the developing cochlea ...
In the developing auditory nerve, mistargeted SGN axons are retracted or pruned and excessive cells are cleared in a process ... In the developing auditory nerve, mistargeted SGN axons are retracted or pruned and excessive cells are cleared in a process ... demonstrate that macrophages contribute to the regulation of glial cell number during postnatal development of the cochlea and ... demonstrate that macrophages contribute to the regulation of glial cell number during postnatal development of the cochlea and ...
Fluid of cochlea. - Auditory nerve axons. - Ipsilateral cochlear nucleus. - Superior olives. - Inferior colliculi ...
dendritic zone (synapses on hair cells of cochlea) telodendria B. Functionally: 1) Motor (Efferent) - related to innervation of ... B. Non-myelinated Axons (, 1 µm; slow conducting): B. NON-MYELINATED AXONS 1) PNS - Non-myelinated axons are embedded in ... Axons: Axons: Axons are neuron processes that project to and synapse with dendrites or cell bodies of other neurons or with non ... Axon 2 . 3) PNS: In the PNS, a typical myelinated axon has the following structure: axon, surrounded by myelin sheath, ...
These findings suggest that GC-B-controlled axon bifurcation of spiral ganglion neurons is important for proper activation of ... Sensory axon T-like branching (bifurcation) in neurons from dorsal root ganglia (DRG) and cranial sensory ganglia (CSG) depends ... Sensory axon T-like branching (bifurcation) in neurons from dorsal root ganglia (DRG) and cranial sensory ganglia (CSG) depends ... and cGKIα expression in its sensory axons (Figure 1B) (Ter-Avetisyan et al., 2014). Also in the adult cochlea, in line with DRG ...
The spiral ganglion sends axons into the cochlear nerve. At the top of the hair cell is a hair bundle containing stereocilia, ... which lead to the spiral ganglion of Corti in the modiolus of the cochlea. ... endings, which lead to the spiral ganglion of Corti in the modiolus of the cochlea. The spiral ganglion sends axons into the ... of nerve cell bodies, the spiral ganglion, located in the modiolus of the cochlea. The neurons of the spiral ganglion are ...
chemorepulsion of dopaminergic neuron axon Source: Ensembl. *cochlea morphogenesis Source: Ensembl. *convergent extension ... negative regulation of axon extension involved in axon guidance Source: Ensembl. *negative regulation of BMP signaling pathway ... planar cell polarity pathway involved in axon guidance Source: Ensembl. *planar cell polarity pathway involved in cardiac ... chemoattraction of serotonergic neuron axon Source: Ensembl. * ... axon guidance Source: UniProtKB. *canonical Wnt signaling ...
2f) and control-inoculated cochleae (Fig. 2e), with no axons in the regions of Hensen cells, inner sulcus, and interdental ... 2d), suggesting that axons grow toward newly formed ectopic hair cells in the cochlea. Nerve processes have been shown to ... An axon (green) extends from the organ of Corti (arrowhead) to ectopic hair cell. d, An axon (green) extends laterally into the ... Axons are extended from the bundle of auditory nerve toward some of the new hair cells, suggesting that the new cells attract ...
1986). Axons of neurons in the DCN that cross the brain stem in the dorsal acoustic striae occupy a medial position in the ... to the cochlea. superior colliculus. evoked responses to clicks are not abolished by removal of all auditory cortex below the ... Some of these axons terminate on cells in the VNLL. all auditory nerve fibers terminate within the cochlear nuclei. Within the ... Along with axons of some cells in the dorsal nucleus. 1983). 1967). the dorsal (DNLL) and ventral (VNLL) nuclei of the lateral ...
Spiral ganglions from each cochlea project via the auditory nerve (VIII) to the ipsilateral cochlea nucleus.. Axons sent to the ... Receptor sense organ of the cochlea which converted sound signals into nerve impulses via CNVIII.. It is sensory for when the ... Densely innervated by about 10 sensory axons (afferent to the brain). Move due to endolymph. Do not make contact with the ... The superior olive projects pack to the cochlea as well as forward to the central pathways.. The inferior colliculus (caudal ...
Rémy Pujol, Régis Nouvian, Marc Lenoir, "Hair cells (cochlea.eu) *^ Ashmore, Jonathan Felix (1987). "A fast motile response in ... Efferent synapses occur on outer hair cells and on afferent axons under inner hair cells. The presynaptic terminal bouton is ... The outer hair cells mechanically amplify low-level sound that enters the cochlea.[6][7] The amplification may be powered by ... Cross-section of the cochlea. The inner hair cells are located at the termination of the "inner hair cell nerves" and the outer ...
1996) in The cochlea, Structure of the mammalian cochlea, eds Dallos P, Popper AN, Fay RR (Springer, New York), pp 44-129. ... may be small bundles of axons rather than individual axons. Because of the uncertainty in the exact number of axons, we rely, ... Possibly, some SGN axons make more than one synapse with an IHC. Also, we are not always able to resolve individual axons in ... One explant was prepared from the middle turn of each cochlea. In the event that both cochleae were used from a single rat, ...
The human cochlea contains on the order of 3,500 inner hair cells and 12,000 outer hair cells at birth. The outer hair cells ... Efferent synapses occur on outer hair cells and on afferent axons under inner hair cells. The presynaptic terminal bouton is ... In mammals, the auditory hair cells are located within the spiral organ of Corti on the thin basilar membrane in the cochlea of ... Housley, G D; Ashmore, J F (1992). "Ionic currents of outer hair cells isolated from the guinea-pig cochlea". The Journal of ...
... named for the spiral shape it shares with the cochlea. These central axons exit the cochlea at its base and form a nerve trunk ... The peripheral axons of auditory nerve fibers form synaptic connections with the hair cells of the cochlea via ribbon synapses ... The axons from the low-frequency region of the cochlea project to the ventral portion of the dorsal cochlear nucleus and the ... "peripheral axon" and the "central axon", respectively. The peripheral process is sometimes referred to as a dendrite, although ...
The vestibulocochlear anastomosis carries the efferent axons into the cochlea, where they innervate the organ of Corti (OC). ... The shell axons often cover 1-2 octaves of tonotopic length. Their terminal arbor is quite sparse, however. All currently known ... Intrinsic LOCS derived axons travel only approximately 1 µm within the organ of Corti, generally spiraling apically. They give ... The Cochlea. New York: Springer. pp. 435-502. ISBN 978-0-387-94449-4. OCLC 33243443. Warr, WB.; Beck, JE.; Neely, ST. (1997). " ...
... particularly in the orientation of stereociliary bundles in the cochlea. Required for polarization and movement of ... planar cell polarity pathway involved in axon guidance Source: Ensembl. *planar cell polarity pathway involved in heart ... particularly in the orientation of stereociliary bundles in the cochlea. Required for polarization and movement of ...
... measurement of neural activity within a cochlea in response to electrical stimulation of the cochlea by electrodes of the ... the neural response is caused by the superposition of single neural responses at the outside of the axon membranes. The ... A cable or lead of electrode assembly 318 extends from stimulator unit 320 to cochlea 316 and terminates in an array of ... Such fluid motion, in turn, activates tiny hair cells (not shown) that line the inside of cochlea 316. Activation of the hair ...
A non-autonomous function of the core PCP protein VANGL2 directs peripheral axon turning in the developing cochlea Satish R. ... Summary: Genetic analysis of AVG pioneer axon guidance in C. elegans reveals that the E3 ubiquitin ligase RPM-1 prevents axon ... Understanding axon guidance: are we nearly there yet? Esther T. Stoeckli. Development 2018 145: dev151415 doi: 10.1242/dev. ... A crucial role for Arf6 in the response of commissural axons to Slit Mariko Kinoshita-Kawada, Hiroshi Hasegawa, Tsunaki Hongu, ...
The perceived loudness, the firing rate of auditory-nerve axons, and the basilar-membrane vibration in the cochlea all grow ... In the chinchillas cochlea, for example, sound-pressure levels ranging over 120 dB are represented as basilar-membrane ... The basilar membrane in the mammalian cochlea exhibits the same behavior (ref. 2; reviewed in ref. 3). Third, a hair bundle ... 4 and 5). Although the active process of the mammalian cochlea is widely believed to involve voltage-dependent cell-body ...
axolemma - outer membrane covering an axon basilar membrane - a membrane in the cochlea that supports the organ of Corti ...
at 8 months, homozygotes show a 69% loss of SGNs in the basal cochlea relative to a ~28% loss observed in wild-type mice ... at 8 months, the numbers of afferent axons per habenular opening are significantly reduced relative to those of wild-type mice ...
The mammalian cochlea has two types of sensory cells; inner hair cells, which receive auditory-nerve afferent innervation, and ... outer hair cells, innervated by efferent axons of the medial olivocochlear (MOC) system. The role of the MOC system in hearing ...
5A), from a noise-exposed unoperated cochlea (Fig. 5B), from a noise-exposed cochlea perfused with IEM-1460 (Fig. 5C), and from ... Each SGN has a myelinated axon with an unbranched dendritic terminal making one synapse with one IHC. Each of these synapses ... At age 13 to 14 wk and with minipump contents already present in the cochlea for ∼2.5 d, two groups of mice were exposed to ... To test the role of CP-AMPARs in NICS, we infused a selective blocker of CP-AMPARs, IEM-1460, directly into the cochlea and ...
The axons of these neurons form the cochlear component of the vestibulocochlear nerve and synapse in the cochlear nuclei in the ... A chain of tiny sensory ganglia that winds through the cochlea of the inner ear. These ganglia contain the cell bodies of the ... Why Pre-Curved Modiolar Hugging Electrodes Only Cover The Basal Turn of The Cochlea and Not Beyond that? ... Consistent with previous findings in the adult mouse cochlea [1, 7], MLCs were identified in similar regions including the ...
The axons of cilia form the auditory nerve that sends auditory signals to the brain ... Cochlea*spiral-shaped. *fluid-filled inner ear structure. *lined with cilia (tiny hairs) that move when vibrated and cause a ...
  • The MOCS gives rise to a frequency-specific innervation of the cochlea, in that MOC fibres terminate on the outer hair cells at the place in the cochlea predicted from the fibres' characteristic frequency, and are thus tonotopically organised in the same fashion as the primary afferent neurons. (wikipedia.org)
  • In addition to these pathways, over which impulses originating in the cochlea reach the cerebral cortex, there are corticofugal connections and interneuronal circuits that, together with ascending projections, provide numerous opportunities at all levels of the auditory system for convergence and divergence of afferent input, serial and parallel processing of information, and feedback modulation. (scribd.com)
  • Herein, "SGN" used without qualification refers to type I.) Each IHC in the rodent cochlea provides the sole afferent presynaptic input to ∼10 to 20 SGNs, depending on species and tonotopic location. (pnas.org)
  • These ganglia are a meshwork of visceral afferent, sympathetic, and parasympathetic axons that coat the lower part of the trachea, its bifurcation, the aorta, the pulmonary trunk, and the coronary arteries. (tabers.com)
  • Such inhibition is more effective for the outer hair cells since efferents end directly on the cell body as opposed to ending on the afferent axons of the inner hair cells. (philippineembassybrunei.net)
  • The central axons form synaptic connections with cells in the cochlear nucleus of the brainstem. (wikipedia.org)
  • Synaptophysin and synaptobrevin 2 associate closely with packaging and storage of synaptic vesicles and transmitter release, and both play important roles in the development of rat cochlea. (ejh.it)
  • 5 , 6 Synaptophysin is a synaptic vesicle-associated protein that provides specific labeling of olivocochlear efferent fibers and terminals in the cochlea. (ejh.it)
  • The anterior thalamic nucleus sends axons to medial cerebral cortices: the cingulate gyrus, the anterior limbic area, and the parahippocampal gyrus. (thefreedictionary.com)
  • Along with the dorsal longitudinal fasciculus, the medial forebrain bundle is the main pathway by which monoaminergic axons from cells in the hindbrain and midbrain reach the striatum, the limbic system, and the cerebral cortices of the forebrain. (tabers.com)
  • Spanning the medial and lateral lengths of the brainstem and midbrain is a complex reticulum of richly interconnected cells with long ascending and descending axons, collectively referred to as the reticular activating system, which is concerned with generalized and selective arousal and activation of the neuroaxis. (brainmind.com)
  • The descending fiber bundles provide direct, bilateral input to the cochlea via anatomically segregated medial and lateral efferent divisions (Warr 1992). (oae.it)
  • Axons of the medial olivocochlear bundle terminate a the base of cell bodies of the outer hair cells. (bhssinc.com)
  • Expression was detected in the outer spiral bundle (OSB), the inner spiral bundle (ISB), and the medial wall of the Deiters' cell of the cochlea at P14, and P28, and in the middle or the basal turn of Corti's organ at P10. (ejh.it)
  • Three type I SGNs (blue arrows) and one type II SGN (green arrow) are seen, together with sections of myelinated fibers (axons from neighboring neurons). (cochlea.eu)
  • About 75% of the fibers cross at the floor of the 4th ventricle and terminate at the OHCs of the contralateral cochlea, while the rest of them remain uncrossed and terminate to the OHCs of the ipsilateral cochlea. (oae.it)
  • Because OAEs are evoked by transient signals that have a wide frequency response, a broad region of the cochlea responds, providing information on the frequency range from 1000 Hz to 4000 Hz. (bhssinc.com)
  • At the ventral midline, developing commissural axons increase Slit sensitivity through a positive-feedback mechanism that is Arf6 mediated and driven by Robo1 receptor endocytic recycling. (biologists.org)
  • Kennedy TESerafini Tde la Torre JRTessier-Lavigne M Netrins are diffusible chemotropic factors for commissural axons in the embryonic spinal cord. (jamanetwork.com)
  • Although both the LOCS and MOCS contain crossed (contralateral) and uncrossed (ipsilateral) fibres, in most mammalian species the majority of LOCS fibres project to the ipsilateral cochlea, whilst the majority of the MOCS fibres project to the contralateral cochlea. (wikipedia.org)
  • The lateral OC bundle arises from neurons within the Lateral Superior Olivary (LSO) nucleus complex in the upper pons and its unmyelinated axons terminate to the inner hair cells (ICHs) mainly (89%-91%) of the ipsilateral cochlea. (oae.it)
  • The OCB contains fibres projecting to both the ipsilateral and contralateral cochleae, prompting an initial division into crossed (COCB) and uncrossed (UCOCB) systems. (wikipedia.org)
  • The tip electrodes of a cochlear implant Type-CI24M, kindly provided by Cochlear AG Basel, Switzerland were inserted into the basal turn of the cochlea and it was aimed to obtain an initial electrically evoked maximal brainstem response amplitude in the range of 5-8 μV. (egms.de)
  • A diffuse limbic tract of lightly myelinated and unmyelinated axons interconnecting the forebrain, hypothalamus, and brainstem. (tabers.com)
  • The ossicles are the three smallest bones in the human body, contained within the middle ear and serving to transmit sounds to the fluid-filled cochlea. (wikipremed.com)