Sciatic Nerve: 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.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.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.Nerve Fibers: Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.Nerve Regeneration: Renewal or physiological repair of damaged nerve tissue.Nerve Block: Interruption of NEURAL CONDUCTION in peripheral nerves or nerve trunks by the injection of a local anesthetic agent (e.g., LIDOCAINE; PHENOL; BOTULINUM TOXINS) to manage or treat pain.Nerve Endings: 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.Sural Nerve: A branch of the tibial nerve which supplies sensory innervation to parts of the lower leg and foot.Median Nerve: A major nerve of the upper extremity. In humans, the fibers of the median nerve originate in the lower cervical and upper thoracic spinal cord (usually C6 to T1), travel via the brachial plexus, and supply sensory and motor innervation to parts of the forearm and hand.Facial Nerve: 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.Nerve Crush: Treatment of muscles and nerves under pressure as a result of crush injuries.Peripheral Nerve Injuries: Injuries to the PERIPHERAL NERVES.Tibial Nerve: The medial terminal branch of the sciatic nerve. The tibial nerve fibers originate in lumbar and sacral spinal segments (L4 to S2). They supply motor and sensory innervation to parts of the calf and foot.Ulnar Nerve: A major nerve of the upper extremity. In humans, the fibers of the ulnar nerve originate in the lower cervical and upper thoracic spinal cord (usually C7 to T1), travel via the medial cord of the brachial plexus, and supply sensory and motor innervation to parts of the hand and forearm.Femoral Nerve: 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.Spinal Nerves: The 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.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.Trigeminal Nerve: 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.Nerve Growth Factors: Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.Phrenic Nerve: 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.Radial Nerve: 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.Cranial Nerves: Twelve pairs of nerves that carry general afferent, visceral afferent, special afferent, somatic efferent, and autonomic efferent fibers.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.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.Ophthalmic Nerve: 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.Nerve Tissue: Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.Mandibular Nerve: A branch of the trigeminal (5th cranial) nerve. The mandibular nerve carries motor fibers to the muscles of mastication and sensory fibers to the teeth and gingivae, the face in the region of the mandible, and parts of the dura.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.Splanchnic Nerves: 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.Glossopharyngeal Nerve: 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.Neural Conduction: The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.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.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.Thoracic Nerves: The twelve spinal nerves on each side of the thorax. They include eleven INTERCOSTAL NERVES and one subcostal nerve. Both sensory and motor, they supply the muscles and skin of the thoracic and abdominal walls.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.Accessory Nerve: 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.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.Abducens Nerve: 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.Oculomotor Nerve: 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.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.Cranial Nerve Neoplasms: Benign and malignant neoplasms that arise from one or more of the twelve cranial nerves.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.Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.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.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Lingual Nerve: A sensory branch of the MANDIBULAR NERVE, which is part of the trigeminal (5th cranial) nerve. The lingual nerve carries general afferent fibers from the anterior two-thirds of the tongue, the floor of the mouth, and the mandibular gingivae.Olfactory Nerve: The 1st cranial nerve. The olfactory nerve conveys the sense of smell. It is formed by the axons of OLFACTORY RECEPTOR NEURONS which project from the olfactory epithelium (in the nasal epithelium) to the OLFACTORY BULB.Hypoglossal Nerve: The 12th cranial nerve. The hypoglossal nerve originates in the hypoglossal nucleus of the medulla and supplies motor innervation to all of the muscles of the tongue except the palatoglossus (which is supplied by the vagus). This nerve also contains proprioceptive afferents from the tongue muscles.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.Abducens Nerve Diseases: Diseases of the sixth cranial (abducens) nerve or its nucleus in the pons. The nerve may be injured along its course in the pons, intracranially as it travels along the base of the brain, in the cavernous sinus, or at the level of superior orbital fissure or orbit. Dysfunction of the nerve causes lateral rectus muscle weakness, resulting in horizontal diplopia that is maximal when the affected eye is abducted and ESOTROPIA. Common conditions associated with nerve injury include INTRACRANIAL HYPERTENSION; CRANIOCEREBRAL TRAUMA; ISCHEMIA; and INFRATENTORIAL NEOPLASMS.Maxillary Nerve: 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.Oculomotor Nerve Diseases: Diseases of the oculomotor nerve or nucleus that result in weakness or paralysis of the superior rectus, inferior rectus, medial rectus, inferior oblique, or levator palpebrae muscles, or impaired parasympathetic innervation to the pupil. With a complete oculomotor palsy, the eyelid will be paralyzed, the eye will be in an abducted and inferior position, and the pupil will be markedly dilated. Commonly associated conditions include neoplasms, CRANIOCEREBRAL TRAUMA, ischemia (especially in association with DIABETES MELLITUS), and aneurysmal compression. (From Adams et al., Principles of Neurology, 6th ed, p270)Nerve Sheath Neoplasms: Neoplasms which arise from nerve sheaths formed by SCHWANN CELLS in the PERIPHERAL NERVOUS SYSTEM or by OLIGODENDROCYTES in the CENTRAL NERVOUS SYSTEM. Malignant peripheral nerve sheath tumors, NEUROFIBROMA, and NEURILEMMOMA are relatively common tumors in this category.Peripheral Nervous System Diseases: Diseases of the peripheral nerves external to the brain and spinal cord, which includes diseases of the nerve roots, ganglia, plexi, autonomic nerves, sensory nerves, and motor nerves.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.Nerve Tissue ProteinsNeurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.Denervation: The resection or removal of the nerve to an organ or part. (Dorland, 28th ed)Sciatic Neuropathy: 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)Cranial Nerve Injuries: Dysfunction of one or more cranial nerves causally related to a traumatic injury. Penetrating and nonpenetrating CRANIOCEREBRAL TRAUMA; NECK INJURIES; and trauma to the facial region are conditions associated with cranial nerve injuries.Chorda Tympani Nerve: A branch of the facial (7th cranial) nerve which passes through the middle ear and continues through the petrotympanic fissure. The chorda tympani nerve carries taste sensation from the anterior two-thirds of the tongue and conveys parasympathetic efferents to the salivary glands.Motor Neurons: Neurons which activate MUSCLE CELLS.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.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.Trigeminal Nerve Diseases: Diseases of the trigeminal nerve or its nuclei, which are located in the pons and medulla. The nerve is composed of three divisions: ophthalmic, maxillary, and mandibular, which provide sensory innervation to structures of the face, sinuses, and portions of the cranial vault. The mandibular nerve also innervates muscles of mastication. Clinical features include loss of facial and intra-oral sensation and weakness of jaw closure. Common conditions affecting the nerve include brain stem ischemia, INFRATENTORIAL NEOPLASMS, and TRIGEMINAL NEURALGIA.Receptor, Nerve Growth Factor: A low affinity receptor that binds NERVE GROWTH FACTOR; BRAIN-DERIVED NEUROTROPHIC FACTOR; NEUROTROPHIN 3; and neurotrophin 4.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)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.Transcutaneous Electric Nerve Stimulation: 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.Peripheral Nervous System Neoplasms: Neoplasms which arise from peripheral nerve tissue. This includes NEUROFIBROMAS; SCHWANNOMAS; GRANULAR CELL TUMORS; and malignant peripheral NERVE SHEATH NEOPLASMS. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp1750-1)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.Laryngeal Nerve Injuries: Traumatic injuries to the LARYNGEAL NERVE.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Obturator Nerve: A nerve originating in the lumbar spinal cord (L2 to L4) and traveling through the lumbar plexus to the lower extremity. The obturator nerve provides motor innervation to the adductor muscles of the thigh and cutaneous sensory innervation of the inner thigh.Brachial Plexus: The large network of nerve fibers which distributes the innervation of the upper extremity. The brachial plexus extends from the neck into the axilla. In humans, the nerves of the plexus usually originate from the lower cervical and the first thoracic spinal cord segments (C5-C8 and T1), but variations are not uncommon.Neuromuscular Junction: The synapse between a neuron and a muscle.Optic Disk: The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.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.Reflex: 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.Optic Nerve Neoplasms: Benign and malignant neoplasms that arise from the optic nerve or its sheath. OPTIC NERVE GLIOMA is the most common histologic type. Optic nerve neoplasms tend to cause unilateral visual loss and an afferent pupillary defect and may spread via neural pathways to the brain.Axotomy: 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.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.Facial Paralysis: Severe or complete loss of facial muscle motor function. This condition may result from central or peripheral lesions. Damage to CNS motor pathways from the cerebral cortex to the facial nuclei in the pons leads to facial weakness that generally spares the forehead muscles. FACIAL NERVE DISEASES generally results in generalized hemifacial weakness. NEUROMUSCULAR JUNCTION DISEASES and MUSCULAR DISEASES may also cause facial paralysis or paresis.Adrenergic Fibers: Nerve fibers liberating catecholamines at a synapse after an impulse.Neuralgia: Intense or aching pain that occurs along the course or distribution of a peripheral or cranial nerve.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.Lumbosacral Plexus: The lumbar and sacral plexuses taken together. The fibers of the lumbosacral plexus originate in the lumbar and upper sacral spinal cord (L1 to S3) and innervate the lower extremities.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.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Afferent Pathways: Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.Lingual Nerve Injuries: Traumatic injuries to the LINGUAL NERVE. It may be a complication following dental treatments.Hypogastric Plexus: A complex network of nerve fibers in the pelvic region. The hypogastric plexus distributes sympathetic fibers from the lumbar paravertebral ganglia and the aortic plexus, parasympathetic fibers from the pelvic nerve, and visceral afferents. The bilateral pelvic plexus is in its lateral extent.Receptor, trkA: A protein-tyrosine kinase receptor that is specific for NERVE GROWTH FACTOR; NEUROTROPHIN 3; neurotrophin 4, neurotrophin 5. It plays a crucial role in pain sensation and thermoregulation in humans. Gene mutations that cause loss of receptor function are associated with CONGENITAL INSENSITIVITY TO PAIN WITH ANHIDROSIS, while gene rearrangements that activate the protein-tyrosine kinase function are associated with tumorigenesis.Trauma, Nervous System: Traumatic injuries to the brain, cranial nerves, spinal cord, autonomic nervous system, or neuromuscular system, including iatrogenic injuries induced by surgical procedures.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.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.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.Diabetic Neuropathies: 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)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.Autonomic Pathways: Nerves and plexuses of the autonomic nervous system. The central nervous system structures which regulate the autonomic nervous system are not included.Neuritis: A general term indicating inflammation of a peripheral or cranial nerve. Clinical manifestation may include PAIN; PARESTHESIAS; PARESIS; or HYPESTHESIA.Muscles: Contractile tissue that produces movement in animals.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.Electromyography: Recording of the changes in electric potential of muscle by means of surface or needle electrodes.Peroneal Neuropathies: Disease involving the common PERONEAL NERVE or its branches, the deep and superficial peroneal nerves. Lesions of the deep peroneal nerve are associated with PARALYSIS of dorsiflexion of the ankle and toes and loss of sensation from the web space between the first and second toe. Lesions of the superficial peroneal nerve result in weakness or paralysis of the peroneal muscles (which evert the foot) and loss of sensation over the dorsal and lateral surface of the leg. Traumatic injury to the common peroneal nerve near the head of the FIBULA is a relatively common cause of this condition. (From Joynt, Clinical Neurology, 1995, Ch51, p31)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)PC12 Cells: A CELL LINE derived from a PHEOCHROMOCYTOMA of the rat ADRENAL MEDULLA. PC12 cells stop dividing and undergo terminal differentiation when treated with NERVE GROWTH FACTOR, making the line a useful model system for NERVE CELL differentiation.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Mechanoreceptors: Cells specialized to transduce mechanical stimuli and relay that information centrally in the nervous system. Mechanoreceptor cells include the INNER EAR hair cells, which mediate hearing and balance, and the various somatosensory receptors, often with non-neural accessory structures.Hypoglossal Nerve Diseases: Diseases of the twelfth cranial (hypoglossal) nerve or nuclei. The nuclei and fascicles of the nerve are located in the medulla, and the nerve exits the skull via the hypoglossal foramen and innervates the muscles of the tongue. Lower brain stem diseases, including ischemia and MOTOR NEURON DISEASES may affect the nuclei or nerve fascicles. The nerve may also be injured by diseases of the posterior fossa or skull base. Clinical manifestations include unilateral weakness of tongue musculature and lingual dysarthria, with deviation of the tongue towards the side of weakness upon attempted protrusion.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Capsaicin: An alkylamide found in CAPSICUM that acts at TRPV CATION CHANNELS.Substance P: 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.Neurilemmoma: A neoplasm that arises from SCHWANN CELLS of the cranial, peripheral, and autonomic nerves. Clinically, these tumors may present as a cranial neuropathy, abdominal or soft tissue mass, intracranial lesion, or with spinal cord compression. Histologically, these tumors are encapsulated, highly vascular, and composed of a homogenous pattern of biphasic fusiform-shaped cells that may have a palisaded appearance. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp964-5)Anesthetics, Local: Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.Synaptic Transmission: 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.Muscle Contraction: 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.Vagotomy: The interruption or removal of any part of the vagus (10th cranial) nerve. Vagotomy may be performed for research or for therapeutic purposes.Olfactory Nerve Injuries: Traumatic injuries to the OLFACTORY NERVE. It may result in various olfactory dysfunction including a complete loss of smell.Evoked Potentials: 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.Physical Stimulation: Act of eliciting a response from a person or organism through physical contact.Hyperalgesia: An increased sensation of pain or discomfort produced by mimimally noxious stimuli due to damage to soft tissue containing NOCICEPTORS or injury to a peripheral nerve.Glaucoma: 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)Ganglia, Autonomic: Clusters of neurons and their processes in the autonomic nervous system. In the autonomic ganglia, the preganglionic fibers from the central nervous system synapse onto the neurons whose axons are the postganglionic fibers innervating target organs. The ganglia also contain intrinsic neurons and supporting cells and preganglionic fibers passing through to other ganglia.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.Nervous System Physiological Phenomena: Characteristic properties and processes of the NERVOUS SYSTEM as a whole or with reference to the peripheral or the CENTRAL NERVOUS SYSTEM.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Ubiquitin Thiolesterase: A thioester hydrolase which acts on esters formed between thiols such as DITHIOTHREITOL or GLUTATHIONE and the C-terminal glycine residue of UBIQUITIN.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Ganglia: Clusters of multipolar neurons surrounded by a capsule of loosely organized CONNECTIVE TISSUE located outside the CENTRAL NERVOUS SYSTEM.Atropine: An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.Motor Endplate: The specialized postsynaptic region of a muscle cell. The motor endplate is immediately across the synaptic cleft from the presynaptic axon terminal. Among its anatomical specializations are junctional folds which harbor a high density of cholinergic receptors.Electrodiagnosis: Diagnosis of disease states by recording the spontaneous electrical activity of tissues or organs or by the response to stimulation of electrically excitable tissue.Ulnar Nerve Compression Syndromes: Ulnar neuropathies caused by mechanical compression of the nerve at any location from its origin at the BRACHIAL PLEXUS to its terminations in the hand. Common sites of compression include the retroepicondylar groove, cubital tunnel at the elbow (CUBITAL TUNNEL SYNDROME), and Guyon's canal at the wrist. Clinical features depend on the site of injury, but may include weakness or paralysis of wrist flexion, finger flexion, and ulnar innervated intrinsic hand muscles, and impaired sensation over the ulnar aspect of the hand, fifth finger, and ulnar half of the ring finger. (Joynt, Clinical Neurology, 1995, Ch51, p43)Sympathectomy: The removal or interruption of some part of the sympathetic nervous system for therapeutic or research purposes.Muscle, Skeletal: 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.Acetylcholine: 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.Nervous System: The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)Stellate Ganglion: A paravertebral sympathetic ganglion formed by the fusion of the inferior cervical and first thoracic ganglia.Carpal Tunnel Syndrome: Entrapment of the MEDIAN NERVE in the carpal tunnel, which is formed by the flexor retinaculum and the CARPAL BONES. This syndrome may be associated with repetitive occupational trauma (CUMULATIVE TRAUMA DISORDERS); wrist injuries; AMYLOID NEUROPATHIES; rheumatoid arthritis (see ARTHRITIS, RHEUMATOID); ACROMEGALY; PREGNANCY; and other conditions. Symptoms include burning pain and paresthesias involving the ventral surface of the hand and fingers which may radiate proximally. Impairment of sensation in the distribution of the median nerve and thenar muscle atrophy may occur. (Joynt, Clinical Neurology, 1995, Ch51, p45)Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Radiculopathy: Disease involving a spinal nerve root (see SPINAL NERVE ROOTS) which may result from compression related to INTERVERTEBRAL DISK DISPLACEMENT; SPINAL CORD INJURIES; SPINAL DISEASES; and other conditions. Clinical manifestations include radicular pain, weakness, and sensory loss referable to structures innervated by the involved nerve root.Accessory Nerve Injuries: Traumatic injuries to the ACCESSORY NERVE. Damage to the nerve may produce weakness in head rotation and shoulder elevation.Pressoreceptors: Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.Hindlimb: Either of two extremities of four-footed non-primate land animals. It usually consists of a FEMUR; TIBIA; and FIBULA; tarsals; METATARSALS; and TOES. (From Storer et al., General Zoology, 6th ed, p73)Sympathetic Fibers, Postganglionic: Nerve fibers which project from sympathetic ganglia to synapses on target organs. Sympathetic postganglionic fibers use norepinephrine as transmitter, except for those innervating eccrine sweat glands (and possibly some blood vessels) which use acetylcholine. They may also release peptide cotransmitters.Oculomotor Nerve Injuries: Traumatic injuries to the OCULOMOTOR NERVE. This may result in various eye movement dysfunction.Cadaver: A dead body, usually a human body.Vagus Nerve Diseases: Diseases of the tenth cranial nerve, including brain stem lesions involving its nuclei (solitary, ambiguus, and dorsal motor), nerve fascicles, and intracranial and extracranial course. Clinical manifestations may include dysphagia, vocal cord weakness, and alterations of parasympathetic tone in the thorax and abdomen.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.Ulnar Neuropathies: Disease involving the ULNAR NERVE from its origin in the BRACHIAL PLEXUS to its termination in the hand. Clinical manifestations may include PARESIS or PARALYSIS of wrist flexion, finger flexion, thumb adduction, finger abduction, and finger adduction. Sensation over the medial palm, fifth finger, and ulnar aspect of the ring finger may also be impaired. Common sites of injury include the AXILLA, cubital tunnel at the ELBOW, and Guyon's canal at the wrist. (From Joynt, Clinical Neurology, 1995, Ch51 pp43-5)Ranvier's Nodes: Regularly spaced gaps in the myelin sheaths of peripheral axons. Ranvier's nodes allow saltatory conduction, that is, jumping of impulses from node to node, which is faster and more energetically favorable than continuous conduction.Carotid Sinus: The dilated portion of the common carotid artery at its bifurcation into external and internal carotids. It contains baroreceptors which, when stimulated, cause slowing of the heart, vasodilatation, and a fall in blood pressure.Diaphragm: The musculofibrous partition that separates the THORACIC CAVITY from the ABDOMINAL CAVITY. Contraction of the diaphragm increases the volume of the thoracic cavity aiding INHALATION.Neurotransmitter Agents: Substances used for their pharmacological actions on any aspect of neurotransmitter systems. Neurotransmitter agents include agonists, antagonists, degradation inhibitors, uptake inhibitors, depleters, precursors, and modulators of receptor function.Dogs: 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)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.Tetrodotoxin: An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.Rats, Inbred Strains: 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.Radial Neuropathy: Disease involving the RADIAL NERVE. Clinical features include weakness of elbow extension, elbow flexion, supination of the forearm, wrist and finger extension, and thumb abduction. Sensation may be impaired over regions of the dorsal forearm. Common sites of compression or traumatic injury include the AXILLA and radial groove of the HUMERUS.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Sensation: The process in which specialized SENSORY RECEPTOR CELLS transduce peripheral stimuli (physical or chemical) into NERVE IMPULSES which are then transmitted to the various sensory centers in the CENTRAL NERVOUS SYSTEM.Lidocaine: A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.Pain Measurement: Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.Neurofilament Proteins: 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)Retina: 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.Chemical Warfare Agents: Chemicals that are used to cause the disturbance, disease, or death of humans during WARFARE.Tongue: 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.Decerebrate State: 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)Median Neuropathy: Disease involving the median nerve, from its origin at the BRACHIAL PLEXUS to its termination in the hand. Clinical features include weakness of wrist and finger flexion, forearm pronation, thenar abduction, and loss of sensation over the lateral palm, first three fingers, and radial half of the ring finger. Common sites of injury include the elbow, where the nerve passes through the two heads of the pronator teres muscle (pronator syndrome) and in the carpal tunnel (CARPAL TUNNEL SYNDROME).Ganglia, Sympathetic: Ganglia of the sympathetic nervous system including the paravertebral and the prevertebral ganglia. Among these are the sympathetic chain ganglia, the superior, middle, and inferior cervical ganglia, and the aorticorenal, celiac, and stellate ganglia.Presynaptic Terminals: The distal terminations of axons which are specialized for the release of neurotransmitters. Also included are varicosities along the course of axons which have similar specializations and also release transmitters. Presynaptic terminals in both the central and peripheral nervous systems are included.Chemoreceptor Cells: Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.Brain Stem: The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.Autonomic Nerve Block: Interruption of sympathetic pathways, by local injection of an anesthetic agent, at any of four levels: peripheral nerve block, sympathetic ganglion block, extradural block, and subarachnoid block.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.Hypesthesia: Absent or reduced sensitivity to cutaneous stimulation.Nociceptors: 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.Penis: The external reproductive organ of males. It is composed of a mass of erectile tissue enclosed in three cylindrical fibrous compartments. Two of the three compartments, the corpus cavernosa, are placed side-by-side along the upper part of the organ. The third compartment below, the corpus spongiosum, houses the urethra.Acetylcholinesterase: An enzyme that catalyzes the hydrolysis of ACETYLCHOLINE to CHOLINE and acetate. In the CNS, this enzyme plays a role in the function of peripheral neuromuscular junctions. EC 184.108.40.206.Medulla Oblongata: The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.GAP-43 Protein: A nervous tissue specific protein which is highly expressed in NEURONS during development and NERVE REGENERATION. It has been implicated in neurite outgrowth, long-term potentiation, SIGNAL TRANSDUCTION, and NEUROTRANSMITTER release. (From Neurotoxicology 1994;15(1):41-7) It is also a substrate of PROTEIN KINASE C.Rabbits: 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.Polyneuropathies: 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.Trigeminal Neuralgia: A syndrome characterized by recurrent episodes of excruciating pain lasting several seconds or longer in the sensory distribution of the TRIGEMINAL NERVE. Pain may be initiated by stimulation of trigger points on the face, lips, or gums or by movement of facial muscles or chewing. Associated conditions include MULTIPLE SCLEROSIS, vascular anomalies, ANEURYSMS, and neoplasms. (Adams et al., Principles of Neurology, 6th ed, p187)Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Evoked Potentials, Somatosensory: The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.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.Cholinergic Fibers: Nerve fibers liberating acetylcholine at the synapse after an impulse.Synaptosomes: Pinched-off nerve endings and their contents of vesicles and cytoplasm together with the attached subsynaptic area of the membrane of the post-synaptic cell. They are largely artificial structures produced by fractionation after selective centrifugation of nervous tissue homogenates.Intraocular Pressure: The pressure of the fluids in the eye.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).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).Rana pipiens: A highly variable species of the family Ranidae in Canada, the United States and Central America. It is the most widely used Anuran in biomedical research.Autonomic Fibers, Postganglionic: Nerve fibers which project from cell bodies of AUTONOMIC GANGLIA to SYNAPSES on target organs.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Autonomic Nervous System: The ENTERIC NERVOUS SYSTEM; PARASYMPATHETIC NERVOUS SYSTEM; and SYMPATHETIC NERVOUS SYSTEM taken together. Generally speaking, the autonomic nervous system regulates the internal environment during both peaceful activity and physical or emotional stress. Autonomic activity is controlled and integrated by the CENTRAL NERVOUS SYSTEM, especially the HYPOTHALAMUS and the SOLITARY NUCLEUS, which receive information relayed from VISCERAL AFFERENTS.Animals, Newborn: Refers to animals in the period of time just after birth.Ligation: Application of a ligature to tie a vessel or strangulate a part.Neurofibroma: A moderately firm, benign, encapsulated tumor resulting from proliferation of SCHWANN CELLS and FIBROBLASTS that includes portions of nerve fibers. The tumors usually develop along peripheral or cranial nerves and are a central feature of NEUROFIBROMATOSIS 1, where they may occur intracranially or involve spinal roots. Pathologic features include fusiform enlargement of the involved nerve. Microscopic examination reveals a disorganized and loose cellular pattern with elongated nuclei intermixed with fibrous strands. (From Adams et al., Principles of Neurology, 6th ed, p1016)Demyelinating Diseases: Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.
"Short latency somatosensory evoked potentials and brain-stem auditory evoked potentials in coma due to CNS depressant drug ... Severe nitrazepam overdose resulting in coma causes the central somatosensory conduction time (CCT) after median nerve ... Brain-stem auditory evoked potentials demonstrate delayed interpeak latencies (IPLs) I-III, III-V and I-V. Toxic overdoses ... A potential hazard following withdrawal of certain benzodiazepines". JAMA: the Journal of the American Medical Association. 241 ...
Electrical stimuli to the auditory nerve evoke a graded excitatory postsynaptic potential in the octopus cells. These EPSPs are ... Auditory nerve fibers, fibers that travel through the auditory nerve (also known as the cochlear nerve or eighth cranial nerve ... Briefly, there are around 30,000 auditory nerve fibres in each of the two auditory nerves. Each fiber is an axon of a spiral ... The major input to the cochlear nucleus is from the auditory nerve, a part of cranial nerve VIII (the vestibulocochlear nerve ...
... after median nerve stimulation being prolonged and the N20 to be dispersed. Brain-stem auditory evoked potentials demonstrate ... "Short latency somatosensory evoked potentials and brain-stem auditory evoked potentials in coma due to CNS depressant drug ... In a New Zealand study (2003) of 200 deaths, Zopiclone, a benzodiazepine receptor agonist, had similar overdose potential as ... for the use of flumazenil in the management of benzodiazepine overdose as the risks in general outweigh any potential benefit ...
His auditory nerve was tested by evoking responses with normal auditory nerve potentials at 10 dB bilaterally. The results of ... Brainstem auditory evoked potentials (BAEP), also referred to as brainstem auditory evoked responses (BAER) show the neuronal ... Auditory middle latency and cortical evoked potentials were grossly abnormal, consistent with the central nature of cortical ... Cortical deafness requires demonstration that brainstem auditory responses are normal, but cortical evoked potentials are ...
Auditory steady state response is an auditory evoked potential, elicited with modulated tones that can be used to predict ... The development of this technique was based on the 8th cranial nerve compound action potential work done by Teas, Eldredge, and ... The auditory brainstem response (ABR) is an auditory evoked potential extracted from ongoing electrical activity in the brain ... Auditory system Bone conduction auditory brainstem response Cochlea EEG Evoked potential Otoacoustic emission Eggermont, Jos J ...
... evoked potential Stereo-elicited visual evoked potential Steady state visually evoked potential Auditory evoked potential can ... Thus evoked compound motor action potentials (CMAP) or sensory nerve action potentials (SNAP) as used in nerve conduction ... visual evoked potential Chromatic visual evoked potential Hemi-field visual evoked potential Flash visual evoked potential LED ... visual evoked potential Motion visual evoked potential Multifocal visual evoked potential Multi-channel visual evoked potential ...
Effect of Sojourn at Altitude of 3,500 m on auditory evoked potential in man S. Mukhopadhyay, L. Thakur, J. P. Anand and W. ... Dr W. Selvamurthy[dead link] Nerve centre. Hinduonnet.com. Retrieved on 2013-03-05.  DU Portal. Du.ac.in. Retrieved on 2013- ... Effect of Sahaja Yoga Meditation on Auditory Evoked Potentials (AEP) and visual contrast sensitivity (VCS) in Epileptics U. ... 1996 Brain stem auditory evoked potentials in epileptics on different antiepileptic Drugs Usha Panjwani, S. H. Singh, W. ...
They reflect neuronal activity in the auditory nerve, cochlear nucleus, superior olive, and inferior colliculus of the ... also called brainstem auditory evoked responses (BAERs), are very small auditory evoked potentials in response to an auditory ... Long, KJ; Allen, N (October 1984). "Abnormal brain-stem auditory evoked potentials following Ondine's curse". Archives of ... In human neuroanatomy, brainstem auditory evoked potentials (BAEPs), ...
An incoming auditory stimulus evokes responses measured in the form of an Event-related potential (ERP), measured brain ... He maintained that upon perception the sound reaches the auditory nerve, brainstem and thalamus. At this point features ... This expert used auditory and motor memory along with conceptual memory. Together the auditory and motor representations allow ... Therefore, there is potential that one's ability to understand and remember will be compromised if one studies with the ...
... form part of the vestibulocochlear nerve (VIIIth cranial nerve, also known as the auditory-vestibular nerve), and project from ... Galambos observed a suppression of the compound action potentials of the AN (referred to as the N1 potential) evoked by low- ... The olivocochlear system is a component of the auditory system involved with the descending control of the cochlea. Its nerve ... Winslow and Sachs (1987) found that stimulating the OCB: "...enables auditory nerve fibres to signal changes in tone level with ...
EMG and evoked potentials, and electrodiagnostic physician focuses mainly on nerve conduction studies, needle EMG, and evoked ... May include visual, auditory, or somatosensory evoked potentials. These record the electrical responses of the brain and spinal ... Physiologists perform the majority of EEGs, evoked potentials and a portion of the nerve conduction studies. They are then ... Many tests involve carrying out an EMG to read the evoked potential recordings. Nerve conduction recordings are extremely ...
The auditory nerve action potential is the most widely studied component in ECochG. The AP represents the summed response of ... Auditory evoked potential Cochlea EEG Electrophysiology Ferraro, John A. (November 15, 2000). "Clinical Electrocochleography: ... Moore EJ (1971). Human cochlear microphonics and auditory nerve action potentials from surface electrodes. Unpublished Ph.D. ... When a certain threshold potential is reached, the spiral ganglion neuron fires an action potential, which enters the auditory ...
Since the 1970s, SSEP (somatosensory evoked potentials) have been used to monitor spinal cord function by stimulating a nerve ... transcranial electrical motor evoked potentials (TCeMEP), EEG, EMG, and auditory brainstem response (ABR). For a given surgery ... and evoked potentials to monitor the functional integrity of certain neural structures (e.g., nerves, spinal cord and parts of ... and nerve surgery. Motor evoked potentials have also been used in surgery for Thoracic aortic aneurysm. Intraoperative ...
Vestibular system Electrophysiology Evoked potential Auditory evoked potential Visual evoked potential Auditory brainstem ... and which was abolished by selective vestibular nerve section. Colebatch et al. (1994) described the basic properties of the ... angular vestibular evoked potentials (VsEPA) and linear vestibular evoked potentials (VsEPL). VsEPA stimuli needs to be a brief ... The vestibular evoked myogenic potential (VEMP or VsEP) is a neurophysiological assessment technique used to determine the ...
Such tests include auditory brainstem evoked potentials (ABR), otoacoustic emissions (OAE) and electrocochleography (ECochG). ... they release neurotransmitter at synapses with the fibers of the auditory nerve, which does produce action potentials. In this ... The sound information from the cochlea travels via the auditory nerve to the cochlear nucleus in the brainstem. From there, the ... Sound is believed to first become consciously experienced at the primary auditory cortex. Around the primary auditory cortex ...
It is possible to assess saccular function through use of the cervical vestibular evoked myogenic potential (cVEMP). The cVEMP ... also known as the statoacoustic nerve or cranial nerve VIII. Within the macula are hair cells, each having a hair bundle on the ... Research has shown, like songbirds, females in some species of fish show seasonal variation in auditory processing and the ... cVEMPs are more unilateral than the closely related ocular vestibular evoked myogenic potential (oVEMP). The most reliable ...
Somatosensory evoked potentials from the stimulation of both posterior nerve and median nerve are normal. The normal SEPs ... to the auditory system. The corollary discharge is used to inhibit the auditory system's response to the cricket's own song and ... Additionally, studies on somatosensory evoked potentials have evidenced that the motor problems are likely related to an ... This decline is because they lack auditory feedback. Another example is acquisition of a new accent as a result of living in an ...
Evoked potential Auditory brainstem response Burkard, R., Don, M., & Eggermont, J. J. Auditory evoked potentials: Basic ... They originally believed that the potential originated from the cochlear nerve, but it was later discovered that the response ... is an evoked potential generated by periodic or nearly-periodic auditory stimuli. Part of the auditory brainstem response (ABR ... "Auditory nonlinearities measured with auditory-evoked potentials". The Journal of the Acoustical Society of America. 87 (3): ...
Evoked potential. *Bereitschaftspotential. *P300. *Auditory evoked potential. *Somatosensory evoked potentials. *Visual evoked ... Neuroregeneration/Nerve regeneration. *Neuroplasticity/Synaptic plasticity *Long-term potentiation. *Long-term depression ... reverse potential of the postsynaptic potential, action potential threshold voltage, ionic permeability of the ion channel, as ... An inhibitory postsynaptic potential (IPSP) is a kind of synaptic potential that makes a postsynaptic neuron less likely to ...
Evoked potential. *Bereitschaftspotential. *P300. *Auditory evoked potential. *Somatosensory evoked potentials. *Visual evoked ... Neurophysiology (from Greek νεῦρον, neuron, "nerve"; φύσις, physis, "nature, origin"; and -λογία, -logia, "knowledge") is a ... In the same year, Bartolomeo Eustachi studied the optic nerve, mainly focusing on its origin in the brain. In 1564, Giulio ... In 1849, Hermann von Helmholtz studied the speed of frog nerve impulses while studying electricity in the body. ...
Evoked potential. *Bereitschaftspotential. *P300. *Auditory evoked potential. *Somatosensory evoked potentials. *Visual evoked ... Neuroregeneration/Nerve regeneration. *Neuroplasticity/Synaptic plasticity *Long-term potentiation. *Long-term depression ... a single pulse of electrical stimulation to fibers of the perforant pathway caused excitatory postsynaptic potentials (EPSPs) ...
Astereognosis and dissociated loss of frontal or parietal components of somatosensory evoked potentials in hemispheric lesions ... Astereognosis is the failure to identify or recognize objects by palpation in the absence of visual or auditory information, ... An individual who cannot properly identify an object using stereognosis, could suffer from lesions in nerve roots, peripheral ... Administered tests and recognition of pattern sensory loss can identify lesions in particular nerves or areas. Yekutiel, M., ...
The ABR, also known as the brainstem auditory evoked response (BAER) test or auditory brainstem evoked potential (ABEP) test ... Warm and cold sensitive nerve fibers differ in structure and function. The cold-sensitive and warm-sensitive nerve fibers are ... When a louder sound is heard, more hair cells are stimulated and the intensity of firing of axons in the cochlear nerve is ... The axons of these single tactile receptors will converge into a single nerve trunk, and the signal is then sent to the spinal ...
An activity-dependent LTP can be evoked in M-cells by a high-frequency stimulation of the VIIIth nerve. Surprisingly, this LTP ... The field potentials of PHP neurons are strongly positive, and form a part of the 'Signature field potential' of the Mauthner ... and also receive auditory input in parallel with the M-cell from the pVIIIth nerve. In fish, water jet stimuli that activate ... This field potential starts with a high-amplitude potential sink up to tens of millivolts in amplitude that originates from the ...
Evoked potential. *Bereitschaftspotential. *P300. *Auditory evoked potential. *Somatosensory evoked potentials. *Visual evoked ... 1.Optic nerve sheath diameter.. The use of optic nerve sheath diameter (ONSD) for the assessment of ICP dates back to ... 8.1 1.Optic nerve sheath diameter.. *8.2 2. Ophthalmodynamometry or the measurement of the retinal venous outflow pressure (VOP ... While the ONSD can at any given point along the optic nerve be measured with a precision of ,1mm, reliability of derived ICP ...
... , like many forms of therapy, has the potential to be a highly culturally sensitive one. Empathy in general is an ... After 1800 books on music therapy often drew on the Brunonian system of medicine, arguing that the stimulation of the nerves ... The sound environment the NICU provides can be disruptive, but music therapy can mask unwanted auditory stimuli and promote a ... Jones, J. D. (2005). A comparison of songwriting and lyric analysis techniques to evoke emotional change in a single session ...
This study investigated the effects of acoustic noise on the auditory nerve compound action potentials in response to electric ... Effects of acoustic noise on the auditory nerve compound action potentials evoked by el.... 20033246 - Electrically evoked ... Electrically evoked compound action potentials (ECAP) were recorded from the auditory nerve trunk in response to electric pulse ... This study investigated the effects of acoustic noise on the auditory nerve compound action potentials in response to electric ...
... or evoked responses, measure the electrophysiologic responses of the nervous system to a variety of stimuli. In theory, almost ... or brainstem auditory evoked response (BAER), measures the functioning of the auditory nerve and auditory pathways in the ... evoked potential (EP) studies-including visual evoked potential (VEP), brainstem auditory evoked potential (BAEP), and ... Brainstem Auditory Evoked Potentials. The brainstem auditory evoked potential (BAEP), ...
Early Acoustic Evoked Potentials.-Somatosensory Evoked Potentials.-Transcranial magnetic stimulation.-Laser evoked potentials.- ... Tinnitus and auditory disturbances.-Intra-axial cranial nerve lesions.-Speech disorders.-Dysphagia.-Ataxia.-Pareses.-Sensory ...
Auditory evoked potential testing indicated absent responses. With the presumptive diagnosis of idiopathic transverse myelitis ... He became comatose on October 5 and had no clinical evidence of cranial nerve function except infrequent spontaneous ... Once rabies was suspected, the patients family was interviewed on October 16 for a history of potential exposure. According to ... Electromyography (EMG) performed at a local outpatient facility on September 24 revealed evidence of axonal nerve damage. ...
Surgery was carried out via a retrosigmoid approach with the brainstem auditory evoked potential (BAEP) guide. Immediately ... Keywords: brainstem auditory evoked potentials; facial nerve; hearing preservation; neurofibromatosis type 2; surgery; ... vestibular schwannoma brainstem auditory evoked potentials; facial nerve; hearing preservation; neurofibromatosis type 2; ... Surgery was carried out via a retrosigmoid approach with the brainstem auditory evoked potential (BAEP) guide. Immediately ...
Evoked Potentials, Auditory/physiology , Hearing Loss, Sensorineural/surgery , Action Potentials , Auditory Threshold/ ... The cochlear implant device has the capacity to measure the electrically evoked compound action potential of the auditory nerve ... Analysis of electrically evoked compound action potential of the auditory nerve in children with bilateral cochlear implants / ... Analysis of electrically evoked compound action potential of the auditory nerve in childre ...
Auditory Evoked Potential (Brain Stem Evoked Potential BSEP). Less commonly used since the advent of magnetic resonance imaging ... Nerve Conduction Studies Nerve conduction studies are used in the diagnosis of nerve entrapments (such as carpal tunnel ... pattern VEPs can be used in conjunction with auditory and somatosensory evoked potential studies. ... Visual Evoked Potentials (VEPs) One of the major uses of VEP is the diagnosis of demyelination, which can cause a marked ...
They reflect neuronal activity in the auditory nerve, cochlear nucleus, superior olive, and inferior colliculus of the ... also called brainstem auditory evoked responses (BAERs), are very small auditory evoked potentials in response to an auditory ... Long, KJ; Allen, N (October 1984). "Abnormal brain-stem auditory evoked potentials following Ondines curse". Archives of ... In human neuroanatomy, brainstem auditory evoked potentials (BAEPs), ...
vestibular evoked myogenic potential (VEMP). This fairly new test assesses parts of the inner ear that the ENG, VNG, and ABR ... This nerve sends signals to the brain that control hearing (auditory function) and help with balance (vestibular function). ... Usually, click-type sounds are amplified through the earphones, and electrodes measure the auditory (hearing) nerves response ... In the eyes, the nerve endings in the retina (at the back of the eye) have light-sensitive cells called rods and cones. When we ...
... including nerve conduction velocity; electromyography (EMG); and visual, auditory and somatosensory evoked potentials. Multiple ... Our Neuromuscular Division coordinates a comprehensive effort to conquer peripheral nerve and muscle disorders, including the ...
Somatosensory evoked potential (SEP) latencies, motor and sensory nerve conduction velocities (CVs), and F-wave latenies were ... auditory and somatosensory evoked potentials. Application of digital signal processing techniques in clinical neurophysiology ... Somatosensory evoked potentials (SEPs) and selected indices of peripheral nerve function were compared in 30 multiple sclerosis ... The relevant variables for study are compound nerve and muscle action potentials, motor unit action potentials, and denervation ...
Phase-locked discharge patterns of single cat auditory-nerve fibers were analyzed in response to complex tones centered at ... Evoked Potentials, Auditory / physiology*. Fourier Analysis. Loudness Perception / physiology. Nerve Fibers / physiology. Pitch ... Phase-locked discharge patterns of single cat auditory-nerve fibers were analyzed in response to complex tones centered at ...
Auditory development *Nerve conduction test. *Latency Auditory evoked potential. *Risk for ADHD *Studies will be included only ... Potential peer reviewers must disclose any financial conflicts of interest greater than $10,000 and any other relevant business ... In addition, recent studies have suggested a potential role for n-3s in some related outcomes, e.g., the development of ... Because of their role as end-users, individuals are invited to serve as key informants and those who present with potential ...
... demonstrating a complete process maturity of the auditory nerve. For waves III and V, there was a gradual decrease of absolute ... The study of brainstem auditory evoked potentials (BAEP) allows obtaining the electrophysiological activity generated in the ... cochlear nerve to the inferior colliculus. In the first months of life, a period of greater neuronal plasticity, important ...
Uusitalo H, Krootila K, Palkama A (1989) Calcitonin gene-related peptide (CGRP) immunoreactive sensory nerves in the human and ... Pietrowsky, R., Dentler, M., Fehm, H.L. et al. Effects of calcitonin on human auditory and visual evoked brain potentials. ... Effects of calcitonin on human auditory and visual evoked brain potentials. *Reinhard Pietrowsky. 1. , ... Effects of calcitonin were assessed on brain potentials recorded from the human scalp which were evoked either by auditory ...
... and evoked potentials. Auditory evoked potentials, visual evoked potentials, and somatosensory evoked potentials are described ... Neurophysiological testing is also examined including nerve conduction velocity testing, electromyography, ... Because of the time and expensive equipment required to administer evoked potentials, the expertise required to interpret them ... evoked potentials are considered research tools at present, although they are a promising instrument in clinical ...
Evoked potentials may be delayed, especially visual evoked potentials. ... Nerve conduction studies reveal a sensory neuropathy greater than motor neuropathy. ... Exaggerated auditory startle responses in multiple system atrophy: a comparative study of parkinson and cerebellar subtypes. ... Nerve conduction studies reveal a sensory neuropathy greater than motor neuropathy.. Evoked potentials may be delayed, ...
Visual evoked potential (VEP). *Brain stem auditory response (BAER). *Nerve conduction velocity/electromyography (NCV/EMG) ...
Auditory. The Brainstem Auditory Evoked Potential (BAEP) assists in evaluating the auditory nerve pathways from the ears ... The Evoked Potential (EP) is a recording of electrical activity from the brain, spinal nerves, or sensory receptors in response ... Somatosensory Evoked Potentials (SSEPs) assess pathways from nerves in the arms or legs, through the spinal cord to the ... Visual Evoked Potentials (VEPs) evaluate the visual nervous system from the eyes to the occipital (visual) cortex of the brain ...
... and finally to the auditory cortex.. Study of interpeak latencies of waveforms of brainstem auditory evoked potentials in ... The evoked potential is generated in the cochlea, goes through the cochlear nerve, through the cochlear nucleus, superior ... Auditory Rehabilitation in Rhesus Macaque Monkeys (Macaca mulatta) with Auditory Brainstem Implants ... One of the hypotheses for the occurrence of tinnitus would be a dysfunction in the efferent auditory system, specifically in ...
Neuroelectrophysiological tests (peripheral nerve conduction velocity, visual, auditory and somatosensory evoked potentials). ...
Nerve conduction studies, Electromyogram, Visual evoked potential, Brainstem *auditory evoked potential, Somatosensory evoked ... potential Employment Opportunities As neuroelectrophysiology is an integral part of neurology, the neuroelectrophysiologists ...
The most common compression syndrome affects the trigeminal nerve and leads to trigeminal neuralgia, followed by hemifacial... ... Neurovascular compression syndromes are clinically characterized by functional disturbances of individual cranial nerves. ... Continuous neuromonitoring with facial nerve EMG and auditory evoked potentials is mandatory (26). This enables the early ... the nervus intermedius and the vestibulocochlear nerve. Very rarely, the oculomotor nerve or the abducens nerve is involved. ...
... interpretation of gross evoked potentials, and models of more central neural processing. A small mean decrement in spike jitter ... We applied a two-pulse forward-masking paradigm to a feline model of the human auditory nerve to assess refractory properties ... Furthermore, refractory data are needed for the development of accurate computational models of auditory nerve fibers. ... Spike amplitude decreased with decreasing MPI, a finding relevant to the development of computational nerve-fiber models, ...
These are visual evoked potentials, brain stem auditory evoked response, and somatosensory evoked potential. Slower nerve ... These are visual evoked potentials, brain stem auditory evoked response, and somatosensory evoked potential. Slower nerve ... Demyelinating neurons, transmit nerve signals slower than non-demyelinated ones and can be detected with EP tests. ... Demyelinating neurons, transmit nerve signals slower than non-demyelinated ones and can be detected with EP tests. ...
Action PotentialsFibersVisualCranial nervesPeripheral nerveDisordersSpinalScalpClinicalSSEPInferior colliculusVestibularElectrodesNervousSensory evoked potThresholdsTumorsDiagnosisNeurons of the auditoryAcousticPathwayFacial nerveVestibulocochlear NerveTranscranialOpticFunctionalElectricalIntraoperative evokedTrigeminalNeuroanatomy
- Effects of acoustic noise on the auditory nerve compound action potentials evoked by electric pulse trains. (biomedsearch.com)
- This study investigated the effects of acoustic noise on the auditory nerve compound action potentials in response to electric pulse trains. (biomedsearch.com)
- Electrically evoked compound action potentials (ECAP) were recorded from the auditory nerve trunk in response to electric pulse trains both during and after the presentation of acoustic white noise. (biomedsearch.com)
- Electrically evoked compound action potentials (ECAPs) reflect the response of the auditory nerve to electrical stimulation while electrocochleography (ECochG) reflects the response of the cochlear hair cells and auditory nerve to acoustic stimulation. (frontiersin.org)
- Thus evoked compound motor action potentials (CMAP) or sensory nerve action potentials (SNAP) as used in nerve conduction studies (NCS) are generally not thought of as evoked potentials, though they do meet the above definition. (wikipedia.org)
- Stimulation with optical radiation evoked compound action potentials from the human auditory nerve. (spie.org)
- Electrically evoked single-fiber action potentials from cat: responses to monopolar, monophasic stimulation. (semanticscholar.org)
- Neurons of the avian nucleus magnocellularis transmit phase-locked action potentials of the auditory nerve in a pathway that contributes to sound localization based on interaural timing differences. (jneurosci.org)
- Furthermore, within the peripheral nervous system, different nerve fibers conduct action potentials at different speeds [ 23 ], and variable frequency and duration [ 24 ], which can affect their tolerance to electrical stimulation regimes. (springer.com)
- action potentials that travel along nerve fibers or muscle fibers. (vin.com)
- In these cases the action potentials consist of active zones which move along a cable-like structure while other parts of the structure remain electrically silent. (vin.com)
- action potentials that arise from nonmoving sources such as nerve cell bodies or their dendrites. (vin.com)
- The clinical aspects of their education will include in-depth training in all practical and theoretical aspects of IONM procedures including: electroencephalography (EEG), electrocorticography (ECoG), functional supratentorial mapping, brainstem auditory evoked potentials (BAEPs), cranial nerve monitoring and mapping, free and triggered electromyography (MEPs), and compound nerve action potentials (CNAPs). (massgeneral.org)
- Phase-locked discharge patterns of single cat auditory-nerve fibers were analyzed in response to complex tones centered at fiber characteristic frequency (CF). Signals were octave-bandwidth harmonic complexes defined by a center frequency F and an intercomponent spacing factor N, such that F/N was the fundamental frequency. (biomedsearch.com)
- The immune system attacks myelin, which is the protective layer around nerve fibers. (healthline.com)
- If you have MS, the protective layer of myelin around your nerve fibers becomes damaged. (healthline.com)
- The refractory characteristics of auditory nerve fibers limit their ability to accurately encode temporal information. (semanticscholar.org)
- Furthermore, refractory data are needed for the development of accurate computational models of auditory nerve fibers. (semanticscholar.org)
- Spontaneous activity of auditory-nerve fibers: insights into stochastic processes at ribbon synapses. (semanticscholar.org)
- Discharge-rate dependence of refractory behavior of cat auditory-nerve fibers. (semanticscholar.org)
- 4. Anatomy Radial arrangement of parts, as of a group of nerve fibers connecting different areas of the brain. (thefreedictionary.com)
- For example, we now know that even with early MS, the nerve fibers themselves (the axons) are affected more than we knew before. (clevelandclinic.org)
- 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. (bioportfolio.com)
- The visual evoked potential (VEP) tests the function of the visual pathway from the retina to the occipital cortex. (medscape.com)
- Effects of calcitonin were assessed on brain potentials recorded from the human scalp which were evoked either by auditory clicks or visual checkerboard pattern-reversals. (springer.com)
- There was also a slight increase in latency of the N80 of the pattern-reversal visual evoked potential (PR-VEP). (springer.com)
- Evoked potentials may be delayed, especially visual evoked potentials. (medscape.com)
- Visual Evoked Potentials (VEPs) evaluate the visual nervous system from the eyes to the occipital (visual) cortex of the brain. (capitalhealth.org)
- Visual evoked potentials (VEP) test. (healthline.com)
- A new finding, to our knowledge, was the normality of visual, somatosensory and auditory evoked potentials. (scielo.org.za)
- Brain stem auditory evoked potentials and visual evoked potentials were abnormal in three (42.9%) and four patients (57.1%), respectively. (bmj.com)
- Visual evoked potentials are used to diagnose visual losses due to optic nerve damage, especially from multiple sclerosis . (thefreedictionary.com)
- The 3 most common types of evoked potential tests include visual (sight), auditory (hearing), and somatosensory (touch). (drugs.com)
- The visual evoked potential (VEP) test measures your brain's response to visual triggers. (drugs.com)
- TMC offers a number of EEG and EVP tests, including BAER (brainstem auditory evoked potential), visual, touch and hearing studies. (tmcaz.com)
- They refer to electrical potentials recorded from scalp overlying visual cortex at the back of the head, which are extracted from the electroencephalogram (EEG) by signal averaging performed by computer. (utah.edu)
- Electroencephalogram, nerve conduction studies, and pattern shift visual-evoked potentials studies are usually normal and brainstem auditory-evoked potentials may vary from normal to minor abnormalities. (orpha.net)
- This test can help identify abnormal areas affected by MS. Visual evoked potential tests are most often used in evaluating MS. (doctors-hospital.net)
- Neurovascular compression syndromes are clinically characterized by functional disturbances of individual cranial nerves. (aerzteblatt.de)
- Other cranial nerves (VII) and the sympathetic system may be involved concurrently. (vetstream.com)
- Disease of cranial nerves IX and X result primarily in dysphagia and laryngeal/pharyngeal problems. (vetstream.com)
- Finding specific neural tissue such as cranial nerves or specific regions of the cerebral cortex are examples of tasks that are included in the subspecialty of intraoperative neurophysiological monitoring. (springer.com)
- Møller AR (1987) Electrophysiological monitoring of cranial nerves in operations in the skull base, in Tumors of the Cranial Base: Diagnosis and Treatment , LN Sekhar and VL Schramm Jr, Editors. (springer.com)
- Current Research and Scholarly Interests Our Neuromuscular Division coordinates a comprehensive effort to conquer peripheral nerve and muscle disorders, including the muscular dystrophies, motor neuron disorders, neuromuscular junction abnormalities, and peripheral neuropathies. (stanford.edu)
- Routine light microscopic and immunocytochemical examination of brain, spinal cord, peripheral nerve, and muscle did not disclose any gross or histologic lesions. (nih.gov)
- As peripheral nerve neuritides they resemble the peripheral neuropathies in pathology and etiology Peripheral nerve: trauma . (vetstream.com)
- VEPs are most useful for testing optic nerve function and less useful for assessing postchiasmatic disorders. (medscape.com)
- Physicians use these tests to diagnose nervous system disorders, locate sites of nerve damage and evaluate a patient's condition after treatment or surgery. (mossrehab.com)
- Disorders diagnosed with auditory EPs include acoustic neuroma (tumors of the inner ear) and multiple sclerosis (chronic disease in which nerves lose patches of their outer covering). (thefreedictionary.com)
- Evoked potential tests, or EVPs, help diagnose disorders of the nervous system, locate the site of nerve damage or brain tumors, evaluate a patient's condition after treatment or to monitor a patient during surgery. (tmcaz.com)
- Evoked Potentials are helpful in evaluating a number of different neurological problems including spinal cord injuries, acoustic neuroma, and optic neuritis. (capitalhealth.org)
- An MS diagnosis requires evidence of demyelination occurring at different times in more than one area of your brain, spinal cord, or optic nerves . (healthline.com)
- Signals can be recorded from cerebral cortex, brain stem, spinal cord and peripheral nerves. (wikipedia.org)
- Multiple sclerosis (MS) is a central nervous system disorder-that is, it affects the brain and spinal cord and spares the nerves and muscles that leave the spinal cord. (clevelandclinic.org)
- In MS, patients develop various areas in the brain and spinal cord where the myelin is stripped off of the nerves. (clevelandclinic.org)
- The nervous system includes the brain, spinal cord and nerves that regulate and coordinate body activities. (stvincent.org)
- Various sized tumors may grow on the nerves in or leading away from the brain and spinal cord (peripheral nerves) and in the vascular system (veins and arteries) and other organ systems. (encyclopedia.com)
- NF-1 affects nerves throughout the body, occurring as groups of soft, fibrous swellings that grow on nerves in the skin, brain, and spinal cord (central nervous system), muscles, and bone. (encyclopedia.com)
- NF-2 is a rare type of NF in which multiple tumors grow on the cranial (head) and spinal nerves and other growths can occur in the brain and spinal cord. (encyclopedia.com)
- In multiple sclerosis, these misdirected immune cells (certain types of lymphocytes, T-cells, B-cells and natural killer cells) attack and consume myelin, damaging the myelin sheath-the fatty insulation surrounding nerve cells in the brain and spinal cord. (healthywomen.org)
- Intraoperative Neurophysiologic Monitoring (IOM) utilizes electrophysiological tests during a surgical procedure with the goal of minimizing the risk of injury to the brain, spinal cord or nerves. (utah.edu)
- MRI scan -This test uses magnetic waves to check for damage to the myelin sheath of the nerves in the brain and spinal cord. (doctors-hospital.net)
- He became comatose on October 5 and had no clinical evidence of cranial nerve function except infrequent spontaneous respiration. (cdc.gov)
- Because of the time and expensive equipment required to administer evoked potentials, the expertise required to interpret them and their status as relative newcomers, evoked potentials are considered research tools at present, although they are a promising instrument in clinical neurotoxicology. (cdc.gov)
- The nerve is especially sensitive to mechanical irritation here, which provokes the clinical symptoms of nerve compression. (aerzteblatt.de)
- Sensory evoked potentials have been widely used in clinical diagnostic medicine since the 1970s, and also in intraoperative neurophysiology monitoring (IONM), also known as surgical neurophysiology. (wikipedia.org)
- Physicians rely on the combined advances in clinical neurophysiology and computer technology at the center to obtain an expansive evaluation of brain, nerve and muscle function. (mossrehab.com)
- These recordings are used in many different clinical situations--the identification of hearing impairment in newborn infants, the detection of tumors on the auditory nerve, the diagnosis of multiple sclerosis. (pluralpublishing.com)
- this book makes an enjoyable reading for those that use some form of auditory evoked potentials for their clinical or research work and are interested in learning about other aspects of such a widespread subject involving neurologists, physiologists, psychologists, neuro-otologists and other specialists and researchers in the field. (pluralpublishing.com)
- Patients with the characteristic radiological white matter disease and typical features (family history, ischaemic events, migraine or dementia) were evaluated for possible CADASIL by means of clinical examination, routine investigations for strokes, magnetic resonance imaging, skin biopsy electron microscopy, evoked potentials and electro-encephalography. (scielo.org.za)
- Introduction: The literature has reported the association between lead and auditory effects,based on clinical and experimental studies. (cdc.gov)
- The authors reviewed patient charts including surgical and clinical records, intraoperative recordings of auditory evoked potentials, records of postoperative auditory examinations, and imaging studies. (thejns.org)
- Recently, new clinical testing of saccular and utricular function have been developed and validated, the so-called vestibular-evoked myogenic potentials - VEMP (Brantberg et al. (bioportfolio.com)
- Vestibular evoked myogenic potentials and their clinical utility in patients with amyotrophic lateral sclerosis. (bioportfolio.com)
- They reflect neuronal activity in the auditory nerve, cochlear nucleus, superior olive, and inferior colliculus of the brainstem. (wikipedia.org)
- The evoked potential is generated in the cochlea, goes through the cochlear nerve, through the cochlear nucleus, superior olivary complex, lateral lemniscus, to the inferior colliculus in the midbrain, on to the medial geniculate body, and finally to the auditory cortex. (thefreedictionary.com)
- I wave originated from the peripheral portion of eighth cranial nerve adjacent to cochlea, II wave from cochlear nucleus, III wave from superior olivary nucleus, IV wave from lateral lemniscus, and V wave from inferior colliculus. (thefreedictionary.com)
- This nerve sends signals to the brain that control hearing (auditory function) and help with balance (vestibular function). (kidshealth.org)
- A literature search was carried out in PubMed with the following search terms: neurovascular compression syndrome, cranial neuralgia, trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia, vestibular nerve compression, vestibular paroxysmia, intermedius neuralgia and microvascular decompression. (aerzteblatt.de)
- A similar, poorly defined idiopathic neuropathy involving the vestibular nerve has been described. (vetstream.com)
- Test-Retest Reliability of ocular vestibular evoked myogenic potentials (oVEMPs) across different electrode montages. (bioportfolio.com)
- The role of vestibular evoked myogenic potentials in multiple sclerosis-related vertigo. (bioportfolio.com)
- To evaluate the diagnostic value of vestibular evoked myogenic potentials (VEMPs) in the assessment of brainstem function integrity in patients with amyotrophic lateral sclerosis (ALS). (bioportfolio.com)
- Is There a Safe Level for Recording Vestibular Evoked Myogenic Potential? (bioportfolio.com)
- There is a growing concern among the scientific community about the possible detrimental effects of signal levels used for eliciting vestibular evoked myogenic potentials (VEMPs) on hearing. (bioportfolio.com)
- Preoperative Assessment of Cervical Vestibular Evoked Myogenic Potentials (cVEMPs) Help in Predicting Hearing Preservation After Removal of Vestibular Schwannomas Through a Middle Fossa Craniotomy. (bioportfolio.com)
- To determine whether cervical vestibular evoked myogenic potentials (cVEMPs) are predictive of hearing preservation in patients undergoing vestibular schwannoma removal through middle fossa craniotomy. (bioportfolio.com)
- The vestibular part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). (bioportfolio.com)
- Vestibular nucleus lying immediately superior to the inferior vestibular nucleus and composed of large multipolar nerve cells. (bioportfolio.com)
- First, the physician conducts a focused history, physical examination and an electrophysiologic evaluation of selected functions of the central nervous system, nerve roots, peripheral nerves, neuromuscular junction and muscles. (mossrehab.com)
- Disease or other damage to the nervous system can affect how well nerves send messages to the brain. (tmcaz.com)
- Nervous system abnormalities and suspected acoustic neuroma , which is a benign tumor of the 8th cranial nerve. (medindia.net)
- Nerve sheath tumors may arise within the trigeminal nerve. (vetstream.com)
- The authors investigated cases of CPA tumors in which the meningioma was inserted in the dura mater in or at the ICA or infiltrated a cranial nerve. (thejns.org)
- In both types of NF, a genetic defect causes these neural crest cells to develop abnormally, resulting in numerous tumors and malformations of the nerves, bones, and skin. (encyclopedia.com)
- Tumors along the optic nerve, causing vision disturbances in about 20 percent of those affected. (encyclopedia.com)
- The characteristic symptoms of NF-2 are due to tumors along the acoustic nerve that result in nerve dysfunction and the loss of hearing. (encyclopedia.com)
- Morphometry of intracellularly labeled neurons of the auditory nerve: correlations with functional properties. (semanticscholar.org)
- Localization of sound based on differences in phase or arrival time of sounds at the two ears requires accurate preservation of timing information by neurons of the auditory system. (jneurosci.org)
- The most common compression syndrome affects the trigeminal nerve and leads to trigeminal neuralgia, followed by hemifacial spasm, which is caused by vascular compression of the facial nerve. (aerzteblatt.de)
- Rarely, primary tumor of VII (nerve sheath tumor, lymphosarcoma Lymphoma , or meningiomas involving the facial nerve are found. (vetstream.com)
- The opposite of a facial paresis, hemifacial spasm is suspected to be due to hypersensitivity of the facial nerve. (vetstream.com)
- The ear on this side is often directed caudally and the palpebral fissure is smaller due to contraction of the muscles innervated by the facial nerve. (vetstream.com)
- If Horner's syndrome or facial nerve paresis are found concurrently, other differentials should be considered. (vetstream.com)
- They could be dissected away from the facial nerve in five cases, whereas in two cases, because of the location of the lesion, the seventh cranial nerve had to be sectioned and repaired with a sural nerve graft. (thejns.org)
- Facial nerve reconstruction by sural grafting was performed in the same operative procedure. (thejns.org)
- Jako G (1965) Facial nerve monitor. (springer.com)
- House J and D Brackmann (1985) Facial nerve grading system. (springer.com)
- Haines SJ and F Torres (1991) Intraoperative monitoring of the facial nerve during decompressive surgery for hemifacial spasm. (springer.com)
- Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. (hindawi.com)
- The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. (hindawi.com)
- Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. (hindawi.com)
- The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. (hindawi.com)
- The accepted underlying pathophysiology of HFS suggests that the disease process is caused by facial nerve root entry zone myelin breakdown and ephaptic transmission, which is the passage of neural impulses through artificial chemical or chemical synapses. (hindawi.com)
- But ears are crucial to maintaining balance thanks to their vestibulocochlear nerve. (kidshealth.org)
- When we turn our heads rapidly, the liquid in the semicircular canals moves the tiny hairs lining the cochlea, sending a message (through the vestibulocochlear nerve) to the brain about the movement. (kidshealth.org)
- Less well-known nerve compression syndromes affect the glossopharyngeal nerve, the nervus intermedius and the vestibulocochlear nerve. (aerzteblatt.de)
- Signals for hearing and balance from the inner ear are carried by the 8th cranial nerve, also called the vestibulocochlear nerve, to a vital part of the brain called the brainstem. (medindia.net)
- BERA is generally used to identify any pathology in the vestibulocochlear nerve or the brainstem. (medindia.net)
- The test detects pathologies from the vestibulocochlear nerve up to the brainstem. (medindia.net)
- When we look at something, light hits the retina, and the rods and cones send electrical signals to the brain through the optic nerve. (kidshealth.org)
- Optical coherence tomography (OCT). OCT is a test that takes a picture of the nerve layers in the back of your eye and can assess thinning of the optic nerve. (healthline.com)
- The b-wave is generated by the mid-retina where editing begins before electrochemical signals are sent into the brain via the optic nerves. (utah.edu)
- In general, slowing neuronal transmission such as produced by myelin plaques, common in multiple sclerosis or gliomas on optic nerves in neurofibromatosis, slow the speed of the VEP wave peaks. (utah.edu)
- Optical coherence tomography (OCT)- A test to evaluate the effect of MS on the optic nerves as well as side effects of some MS treatments. (doctors-hospital.net)
- A small electrical current is applied to the skin overlying nerves on the arms or legs. (capitalhealth.org)
- When the myelin is off, the electrical conduction of these nerves is altered. (clevelandclinic.org)
- Nerves convey information to the body by sending electrical signals down the length of the nerve. (thefreedictionary.com)
- This causes changes in the electrical potential in the nerves. (thefreedictionary.com)
- With the cornea constantly positive, movement of the eye produces a shift of this electrical potential. (utah.edu)