| GLOSSARY - N | |
|---|---|
| Neocerebellum | Phylogenetically newest part of the cerebellum, present in mammals and especially well developed in humans; involved in coordinating precise voluntary movements and also in motor planning; consists of the cortex of the cerebellar hemispheres (but not the paravermal zone) and the dentate deep (intracerebellar) nucleus (also called cerebrocerebellum) |
| Neocortex | Phylogenetically newest part of the cerebral cortex, consisting of six layers (and sublayers) characteristic of mammals and constituting most of the cerebral cortex in humans |
| Neostriatum | The phylogenetically newer part of the basal ganglia consisting of the caudate nucleus and putamen; also called the striatum |
| Nerve fiber | Axonal cell process, plus myelin sheath if present |
| Neuron | The basic structural unit of the nervous system, consisting of the nerve cell body and its processes -- dendrites and axon |
| Neuropil | An area between nerve cells consisting of a complex arrangement of nerve cell processes, including axon terminals, dendrites and synapses |
| Node of Ranvier | Gap in myelin sheath between two successive internodes; necessary for saltatory (rapid) conduction |
| Nodulus | Folium of the vermis; part of the flocculonodular lobe; a useful landmark when the cerebellar cortex is displayed as a flattened surface |
| NUCLEUS | |
| Nucleus | (plural = nuclei) An aggregation of neurons within the CNS (Note: Brief definitions are given as each is defined separately in the Glossary; the listing does not include the cranial nerve nuclei.); in histology, the nucleus of a cell |
| Accessory cuneate | relay nucleus of lower medulla for proprioception to the cerebellum |
| Accumbens | limbic nucleus involved with addictive behavior |
| Ambiguus | motor nucleus located in the medulla for CN IX and X |
| Cuneate (cuneatus) | relay nucleus in the medulla for discriminative touch, proprioception & vibration |
| Dentate | deep cerebellar (intracerebellar) nucleus |
| Dorsal nucleus | (of Clarke) relay nucleus for proprioception in the spinal cord |
| Emboliform | deep cerebellar (intracerebellar) nucleus |
| Fasitigial | deep cerebellar (intracerebellar) nucleus |
| Gracile (gracilis) | relay nucleus in the medulla for discriminative touch, proprioception & vibration |
| Hypothalamic | nuclei for autonomic control, the regulation of water, temperature, food intake and other basic ‘drives’, and involved with the limbic system |
| Interposed | (of cerebellum); formed by the globose and emboliform nuclei |
| Pontine | relay nuclei of the pons from cortex to contralateral cerebellum |
| Proper sensory | relay nucleus of the dorsal horn of spinal cord for pain & temperature |
| Raphe | reticular nuclei in the brainstem located in the midline; serotonergic |
| Raphe magnus | one of the raphe nuclei; involved in the descending regulation of pain |
| Reticular | nuclei of the brainstem, medial, lateral, and raphe, forming the reticular formation of the brainstem; also reticular nucleus of the thalamus |
| Septal | limbic nuclei located under the septal cortex; form part of the septal region |
| Thalamic | specific relay, association and non-specific nuclei |