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Related to thalamic nucleus: lateral nucleus of thalamus
Any of the more than 27 nuclei of the thalamus. The thalamic nuclei are named according to their position in the thalamus, and the medial and dorsal nuclei are separated from the lateral and ventral nuclei by a partitioning layer of axons, called the internal medullary lamina. The thalamic nuclei filter and modify the signals that the nervous system sends to the cerebral cortices. Thalamic nuclei can be divided into five groups by their patterns of connectivity: (a) The nuclei in the base of the thalamus -- the ventroposterior (also called, ventrobasal), the lateral geniculate, and the medial geniculate nuclei -- receive all the sensory information from the body, except olfaction, and send information to the primary sensory areas of the cerebral cortices. (b) The ventral anterior and ventral lateral nuclei (the VA-VL complex) receive motor programs from the globus pallidus (of the basal ganglia) and the cerebellum and send information to the motor areas of the cerebral cortices. (c) The dorsomedial nucleus, the lateral posterior and lateral dorsal nuclei, and the pulvinar nucleus receive information from the association areas of the cerebral cortices and from noncortical regions of the brain and send information back to the association cortices. (d) The anterior nucleus -- part of the limbic circuitry -- receives information from the mammillary body and from the fornix and sends information to the cingulate gyrus of the cerebral cortex. (e) The small nuclei in the internal medullary lamina (intralaminar nuclei) and the nuclei along the midline of the thalamus receive information from the cerbral cortices, the cererebellum, the reticular formation, and elsewhere and send information widely throughout the cerebral cortices.
See also: nucleus
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