| neural tube | <embryology> The progenitor of the central nervous system. See: neural plate, neurulation. (18 Nov 1997) |
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| neural tube defect | <neurology, paediatrics> Abnormal development during embryonic life of the neural tube producing congenital malformations of the nervous system due to closure failure of the neural tube. The structure gives rise to the central nervous system (the brain and spinal cord), and failure to close results in anencephaly (absence of the cranial vault and absence of most or all of the cerebral hemispheres of the brain) and spina bifida or meningomyelocele (open spina with exposure and protusion of the spinal cord). The risk of neuroal tube defects can be decreased by the mother taking folic acid during pregnancy. (04 Jul 1999) |
| dorsal plate of neural tube | The thin layer of the embryonic neural tube connecting the alar plate's dorsally. Synonym: dorsal plate of neural tube. (05 Mar 2000) |
| dorsolateral plate of neural tube | The dorsal division of the lateral walls of the neural tube in the embryo; it gives rise to neurons relaying afferent impulses to higher centres; in the adult such neurons compose the sensory nuclei of the spinal cord and brainstem. Synonym: lamina alaris, alar plate of neural tube, dorsolateral plate of neural tube, lamina dorsalis, wing plate. (05 Mar 2000) |
| ganglia, sensory | Clusters of neurons in the somatic peripheral nervous system which contain the cell bodies of sensory nerve axons. Sensory ganglia may also have intrinsic interneurons and non-neuronal supporting cells. (12 Dec 1998) |
| receptors, sensory | Specialised neurons or parts of neurons which transduce sensory information and relay it centrally. Included are receptors for stimuli outside the body (exteroceptors) as well as receptors for stimuli from within the body itself (interoceptors and proprioceptors). Sensory receptors may include accessory structures which condition (e.g., filter) the input received by the receptor neurons themselves. (12 Dec 1998) |
| principal sensory nucleus of the trigeminus | <anatomy, nerve> The term commonly used to designate the nucleus pontis nervi trigeminalis; located in pons lateral to the motor trigeminal nucleus; receives primary sensory (touch and pressure) input via the trigeminal nerve, projects to ventral posteromedial nucleus of thalamus. Synonym: nucleus sensorius principalis nervi trigemini, nucleus sensorius superior nervi trigemini, principal sensory nucleus of the trigeminus. (05 Mar 2000) |
| principal sensory nucleus of trigeminal nerve | <anatomy, nerve> The term commonly used to designate the nucleus pontis nervi trigeminalis; located in pons lateral to the motor trigeminal nucleus; receives primary sensory (touch and pressure) input via the trigeminal nerve, projects to ventral posteromedial nucleus of thalamus. Synonym: nucleus sensorius principalis nervi trigemini, nucleus sensorius superior nervi trigemini, principal sensory nucleus of the trigeminus. (05 Mar 2000) |
| hereditary sensory radicular neuropathy | Neuropathy characterised by the occurrence of severe, relapsing foot ulcerations of neuropathic origin, destruction of terminal digits of feet and hands, and a loss of sensation; autosomal dominant inheritance is associated with onset in the second decade or later. (05 Mar 2000) |
| secondary sensory cortex | A cortical region occupying the parietal operculum (upper lip of the lateral sulcus) closely posterior to the foot of the postcentral gyrus; like the primary somatic-sensory cortex of the postcentral gyrus, this region receives sensory impulses originating in face, trunk, and limbs; projections to the s.s.c. Are from the ventral basal complex (ventral posteromedial and posterolateral thalamic nuclei) and from the primary somesthetic cortex. (05 Mar 2000) |
| secondary sensory nuclei | Nuclei terminales, collective term indicating those nerve cell groups in the rhombencephalon and spinal cord in which the afferent fibres of the spinal and cranial nerves terminate. Synonym: nuclei terminationis, secondary sensory nuclei. (05 Mar 2000) |
| sensory | <otolaryngology> Pertaining to or subserving sensation. Origin: L. Sensorius (18 Nov 1997) |
| sensory amblyopia | A suppression of central vision in one eye due to faulty image formation; for example, by a corneal scar, a cataract, or a droopy eyelid. Synonym: deprivation amblyopia. (05 Mar 2000) |
| sensory amusia | Inability to interpret or appreciate musical sounds. (05 Mar 2000) |
| sensory aphasia | Aphasia in which there is impairment in the comprehension of spoken and written words, associated with effortless, articulated, but paraphrasic, speech and writing; malformed words, substitute words, and enologisms are charcteristic. When severe, and speech is incomprehensible, it is called jargon aphasia. The patient often appears unaware of his deficit. Synonym: fluent aphasia, impressive aphasia, posterior aphasia, psychosensory aphasia, receptive aphasia, Wernicke's aphasia. (05 Mar 2000) |