Nerve Fibers, Myelinated
A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the myelinated nerve fibers are completely encased in a MYELIN SHEATH. They are fibers of relatively large and varied diameters. Their NEURAL CONDUCTION rates are faster than those of the unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED). Myelinated nerve fibers are present in somatic and autonomic nerves.
A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.
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.
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.
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.
A branch of the tibial nerve which supplies sensory innervation to parts of the lower leg and foot.
Renewal or physiological repair of damaged nerve tissue.
Nerve Fibers, Unmyelinated
A class of nerve fibers as defined by their nerve sheath arrangement. The AXONS of the unmyelinated nerve fibers are small in diameter and usually several are surrounded by a single MYELIN SHEATH. They conduct low-velocity impulses, and represent the majority of peripheral sensory and autonomic fibers, but are also found in the BRAIN and SPINAL CORD.
Spinal Nerve Roots
Paired bundles of NERVE FIBERS entering and leaving the SPINAL CORD at each segment. The dorsal and ventral nerve roots join to form the mixed segmental spinal nerves. The dorsal roots are generally afferent, formed by the central projections of the spinal (dorsal root) ganglia sensory cells, and the ventral roots are efferent, comprising the axons of spinal motor and PREGANGLIONIC AUTONOMIC FIBERS.
Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.
Branch-like terminations of NERVE FIBERS, sensory or motor NEURONS. Endings of sensory neurons are the beginnings of afferent pathway to the CENTRAL NERVOUS SYSTEM. Endings of motor neurons are the terminals of axons at the muscle cells. Nerve endings which release neurotransmitters are called PRESYNAPTIC TERMINALS.
Optic Nerve Diseases
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
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.
Muscle Fibers, Skeletal
Large, multinucleate single cells, either cylindrical or prismatic in shape, that form the basic unit of SKELETAL MUSCLE. They consist of MYOFIBRILS enclosed within and attached to the SARCOLEMMA. They are derived from the fusion of skeletal myoblasts (MYOBLASTS, SKELETAL) into a syncytium, followed by differentiation.
Peripheral Nerve Injuries
Injuries to the PERIPHERAL NERVES.
Treatment of muscles and nerves under pressure as a result of crush injuries.
The 7th cranial nerve. The facial nerve has two parts, the larger motor root which may be called the facial nerve proper, and the smaller intermediate or sensory root. Together they provide efferent innervation to the muscles of facial expression and to the lacrimal and SALIVARY GLANDS, and convey afferent information for TASTE from the anterior two-thirds of the TONGUE and for TOUCH from the EXTERNAL EAR.
Tomography, Optical Coherence
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Peripheral Nervous System Diseases
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)
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.
The 5th and largest cranial nerve. The trigeminal nerve is a mixed motor and sensory nerve. The larger sensory part forms the ophthalmic, mandibular, and maxillary nerves which carry afferents sensitive to external or internal stimuli from the skin, muscles, and joints of the face and mouth and from the teeth. Most of these fibers originate from cells of the TRIGEMINAL GANGLION and project to the TRIGEMINAL NUCLEUS of the brain stem. The smaller motor part arises from the brain stem trigeminal motor nucleus and innervates the muscles of mastication.
Sensory Receptor Cells
A sensory branch of the trigeminal (5th cranial) nerve. The ophthalmic nerve carries general afferents from the superficial division of the face including the eyeball, conjunctiva, upper eyelid, upper nose, nasal mucosa, and scalp.
Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.
Nerve Growth Factors
A nerve originating in the lumbar spinal cord (usually L2 to L4) and traveling through the lumbar plexus to provide motor innervation to extensors of the thigh and sensory innervation to parts of the thigh, lower leg, and foot, and to the hip and knee joints.
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.
Type III intermediate filament proteins that assemble into neurofilaments, the major cytoskeletal element in nerve axons and dendrites. They consist of three distinct polypeptides, the neurofilament triplet. Types I, II, and IV intermediate filament proteins form other cytoskeletal elements such as keratins and lamins. It appears that the metabolism of neurofilaments is disturbed in Alzheimer's disease, as indicated by the presence of neurofilament epitopes in the neurofibrillary tangles, as well as by the severe reduction of the expression of the gene for the light neurofilament subunit of the neurofilament triplet in brains of Alzheimer's patients. (Can J Neurol Sci 1990 Aug;17(3):302)
A major nerve of the upper extremity. In humans the fibers of the radial nerve originate in the lower cervical and upper thoracic spinal cord (usually C5 to T1), travel via the posterior cord of the brachial plexus, and supply motor innervation to extensor muscles of the arm and cutaneous sensory fibers to extensor regions of the arm and hand.
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.
Long, pliable, cohesive natural or manufactured filaments of various lengths. They form the structure of some minerals. The medical significance lies in their potential ability to cause various types of PNEUMOCONIOSIS (e.g., ASBESTOSIS) after occupational or environmental exposure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p708)
Calcitonin Gene-Related Peptide
Calcitonin gene-related peptide. A 37-amino acid peptide derived from the calcitonin gene. It occurs as a result of alternative processing of mRNA from the calcitonin gene. The neuropeptide is widely distributed in neural tissue of the brain, gut, perivascular nerves, and other tissue. The peptide produces multiple biological effects and has both circulatory and neurotransmitter modes of action. In particular, it is a potent endogenous vasodilator.
The 9th cranial nerve. The glossopharyngeal nerve is a mixed motor and sensory nerve; it conveys somatic and autonomic efferents as well as general, special, and visceral afferents. Among the connections are motor fibers to the stylopharyngeus muscle, parasympathetic fibers to the parotid glands, general and taste afferents from the posterior third of the tongue, the nasopharynx, and the palate, and afferents from baroreceptors and CHEMORECEPTOR CELLS of the carotid sinus.
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
Nerve Growth Factor
NERVE GROWTH FACTOR is the first of a series of neurotrophic factors that were found to influence the growth and differentiation of sympathetic and sensory neurons. It is comprised of alpha, beta, and gamma subunits. The beta subunit is responsible for its growth stimulating activity.
Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.
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.
The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.
Muscle Fibers, Slow-Twitch
Muscle Fibers, Fast-Twitch
Peripheral AFFERENT NEURONS which are sensitive to injuries or pain, usually caused by extreme thermal exposures, mechanical forces, or other noxious stimuli. Their cell bodies reside in the DORSAL ROOT GANGLIA. Their peripheral terminals (NERVE ENDINGS) innervate target tissues and transduce noxious stimuli via axons to the CENTRAL NERVOUS SYSTEM.
Nerve Compression Syndromes
Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.
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.
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).
A TEXTILE fiber obtained from the pappus (outside the SEEDS) of cotton plant (GOSSYPIUM). Inhalation of cotton fiber dust over a prolonged period can result in BYSSINOSIS.
Peripheral Nervous System
The nervous system outside of the brain and spinal cord. The peripheral nervous system has autonomic and somatic divisions. The autonomic nervous system includes the enteric, parasympathetic, and sympathetic subdivisions. The somatic nervous system includes the cranial and spinal nerves and their ganglia and the peripheral sensory receptors.
An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses.
Neurons which send impulses peripherally to activate muscles or secretory cells.
Diagnostic Techniques, Ophthalmological
An alkylamide found in CAPSICUM that acts at TRPV CATION CHANNELS.
Sympathetic Nervous System
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.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
Disease or damage involving the SCIATIC NERVE, which divides into the PERONEAL NERVE and TIBIAL NERVE (see also PERONEAL NEUROPATHIES and TIBIAL NEUROPATHY). Clinical manifestations may include SCIATICA or pain localized to the hip, PARESIS or PARALYSIS of posterior thigh muscles and muscles innervated by the peroneal and tibial nerves, and sensory loss involving the lateral and posterior thigh, posterior and lateral leg, and sole of the foot. The sciatic nerve may be affected by trauma; ISCHEMIA; COLLAGEN DISEASES; and other conditions. (From Adams et al., Principles of Neurology, 6th ed, p1363)
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).
Recurrent Laryngeal Nerve
Branches of the vagus (tenth cranial) nerve. The recurrent laryngeal nerves originate more caudally than the superior laryngeal nerves and follow different paths on the right and left sides. They carry efferents to all muscles of the larynx except the cricothyroid and carry sensory and autonomic fibers to the laryngeal, pharyngeal, tracheal, and cardiac regions.
Visual Field Tests
Microscopy, Electron, Transmission
Optic Nerve Injuries
Injuries to the optic nerve induced by a trauma to the face or head. These may occur with closed or penetrating injuries. Relatively minor compression of the superior aspect of orbit may also result in trauma to the optic nerve. Clinical manifestations may include visual loss, PAPILLEDEMA, and an afferent pupillary defect.
Peripheral, autonomic, and cranial nerve disorders that are associated with DIABETES MELLITUS. These conditions usually result from diabetic microvascular injury involving small blood vessels that supply nerves (VASA NERVORUM). Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy (see OCULOMOTOR NERVE DISEASES); MONONEUROPATHY; mononeuropathy multiplex; diabetic amyotrophy; a painful POLYNEUROPATHY; autonomic neuropathy; and thoracoabdominal neuropathy. (From Adams et al., Principles of Neurology, 6th ed, p1325)
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.
Scanning Laser Polarimetry
Transection or severing of an axon. This type of denervation is used often in experimental studies on neuronal physiology and neuronal death or survival, toward an understanding of nervous system disease.
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)
The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.
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.
A plant genus of the family FABACEAE that is the source of mucuna gum.
A class of large neuroglial (macroglial) cells in the central nervous system. Oligodendroglia may be called interfascicular, perivascular, or perineuronal (not the same as SATELLITE CELLS, PERINEURONAL of GANGLIA) according to their location. They form the insulating MYELIN SHEATH of axons in the central nervous system.
Cell Adhesion Molecules, Neuronal
Surface ligands that mediate cell-to-cell adhesion and function in the assembly and interconnection of the vertebrate nervous system. These molecules promote cell adhesion via a homophilic mechanism. These are not to be confused with NEURAL CELL ADHESION MOLECULES, now known to be expressed in a variety of tissues and cell types in addition to nervous tissue.
Central Nervous System
Myelin Basic Protein
An abundant cytosolic protein that plays a critical role in the structure of multilamellar myelin. Myelin basic protein binds to the cytosolic sides of myelin cell membranes and causes a tight adhesion between opposing cell membranes.
The 11th cranial nerve which originates from NEURONS in the MEDULLA and in the CERVICAL SPINAL CORD. It has a cranial root, which joins the VAGUS NERVE (10th cranial) and sends motor fibers to the muscles of the LARYNX, and a spinal root, which sends motor fibers to the TRAPEZIUS and the sternocleidomastoid muscles.
A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.
Rats, Inbred Strains
An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
Kv1.1 Potassium Channel
The intermediate sensory division of the trigeminal (5th cranial) nerve. The maxillary nerve carries general afferents from the intermediate region of the face including the lower eyelid, nose and upper lip, the maxillary teeth, and parts of the dura.
Vasoactive Intestinal Peptide
A highly basic, 28 amino acid neuropeptide released from intestinal mucosa. It has a wide range of biological actions affecting the cardiovascular, gastrointestinal, and respiratory systems and is neuroprotective. It binds special receptors (RECEPTORS, VASOACTIVE INTESTINAL PEPTIDE).
MYELIN-specific proteins that play a structural or regulatory role in the genesis and maintenance of the lamellar MYELIN SHEATH structure.
Chorda Tympani Nerve
Disease Models, Animal
The 3d cranial nerve. The oculomotor nerve sends motor fibers to the levator muscles of the eyelid and to the superior rectus, inferior rectus, and inferior oblique muscles of the eye. It also sends parasympathetic efferents (via the ciliary ganglion) to the muscles controlling pupillary constriction and accommodation. The motor fibers originate in the oculomotor nuclei of the midbrain.
The lateral of the two terminal branches of the sciatic nerve. The peroneal (or fibular) nerve provides motor and sensory innervation to parts of the leg and foot.
Mossy Fibers, Hippocampal
Axons of certain cells in the DENTATE GYRUS. They project to the polymorphic layer of the dentate gyrus and to the proximal dendrites of PYRAMIDAL CELLS of the HIPPOCAMPUS. These mossy fibers should not be confused with mossy fibers that are cerebellar afferents (see NERVE FIBERS).
Receptors, Nerve Growth Factor
Cell surface receptors that bind NERVE GROWTH FACTOR; (NGF) and a NGF-related family of neurotrophic factors that includes neurotrophins, BRAIN-DERIVED NEUROTROPHIC FACTOR and CILIARY NEUROTROPHIC FACTOR.
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 sensation of cold, heat, coolness, and warmth as detected by THERMORECEPTORS.
A hereditary motor and sensory neuropathy transmitted most often as an autosomal dominant trait and characterized by progressive distal wasting and loss of reflexes in the muscles of the legs (and occasionally involving the arms). Onset is usually in the second to fourth decade of life. This condition has been divided into two subtypes, hereditary motor and sensory neuropathy (HMSN) types I and II. HMSN I is associated with abnormal nerve conduction velocities and nerve hypertrophy, features not seen in HMSN II. (Adams et al., Principles of Neurology, 6th ed, p1343)
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.
Receptor, Nerve Growth Factor
A low affinity receptor that binds NERVE GROWTH FACTOR; BRAIN-DERIVED NEUROTROPHIC FACTOR; NEUROTROPHIN 3; and neurotrophin 4.
Modified epidermal cells located in the stratum basale. They are found mostly in areas where sensory perception is acute, such as the fingertips. Merkel cells are closely associated with an expanded terminal bulb of an afferent myelinated nerve fiber. Do not confuse with Merkel's corpuscle which is a combination of a neuron and an epidermal cell.
Intense or aching pain that occurs along the course or distribution of a peripheral or cranial nerve.
A muscular organ in the mouth that is covered with pink tissue called mucosa, tiny bumps called papillae, and thousands of taste buds. The tongue is anchored to the mouth and is vital for chewing, swallowing, and for speech.
The 6th cranial nerve which originates in the ABDUCENS NUCLEUS of the PONS and sends motor fibers to the lateral rectus muscles of the EYE. Damage to the nerve or its nucleus disrupts horizontal eye movement control.
A 36-amino acid peptide present in many organs and in many sympathetic noradrenergic neurons. It has vasoconstrictor and natriuretic activity and regulates local blood flow, glandular secretion, and smooth muscle activity. The peptide also stimulates feeding and drinking behavior and influences secretion of pituitary hormones.
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.
Facial Nerve Injuries
Traumatic injuries to the facial nerve. This may result in FACIAL PARALYSIS, decreased lacrimation and salivation, and loss of taste sensation in the anterior tongue. The nerve may regenerate and reform its original pattern of innervation, or regenerate aberrantly, resulting in inappropriate lacrimation in response to gustatory stimuli (e.g., "crocodile tears") and other syndromes.
Cranial Nerve Neoplasms
Benign and malignant neoplasms that arise from one or more of the twelve cranial nerves.
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.
Facial Nerve Diseases
Diseases of the facial nerve or nuclei. Pontine disorders may affect the facial nuclei or nerve fascicle. The nerve may be involved intracranially, along its course through the petrous portion of the temporal bone, or along its extracranial course. Clinical manifestations include facial muscle weakness, loss of taste from the anterior tongue, hyperacusis, and decreased lacrimation.
A tumor made up of nerve cells and nerve fibers. (Dorland, 27th ed)
Parasympathetic Nervous System
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.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Fluorescent Antibody Technique
Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.
Diseases of multiple peripheral nerves simultaneously. Polyneuropathies usually are characterized by symmetrical, bilateral distal motor and sensory impairment with a graded increase in severity distally. The pathological processes affecting peripheral nerves include degeneration of the axon, myelin or both. The various forms of polyneuropathy are categorized by the type of nerve affected (e.g., sensory, motor, or autonomic), by the distribution of nerve injury (e.g., distal vs. proximal), by nerve component primarily affected (e.g., demyelinating vs. axonal), by etiology, or by pattern of inheritance.
Nerves and plexuses of the autonomic nervous system. The central nervous system structures which regulate the autonomic nervous system are not included.
Kv1.2 Potassium Channel
Skeletal muscle structures that function as the MECHANORECEPTORS responsible for the stretch or myotactic reflex (REFLEX, STRETCH). They are composed of a bundle of encapsulated SKELETAL MUSCLE FIBERS, i.e., the intrafusal fibers (nuclear bag 1 fibers, nuclear bag 2 fibers, and nuclear chain fibers) innervated by SENSORY NEURONS.