The inner core of an intervertebral disc. (See SPINAL COLUMN.)
a collection of grey matter, shaped like a biconvex lens, lying beneath the *thalamus and close to the *corpus striatum, to which it is connected by nerve tracts. It has connections with the cerebral cortex and several other nuclei nearby. Stimulation of this nucleus is now being used in the treatment of Parkinson’s disease.... subthalamic nucleus
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