n. part of the forebrain, consisting of a narrow band of nerve tissue in the roof of the third ventricle (including the region where the choroid plexus is attached) and the *pineal gland. See also brain.
n. an anatomical division of the forebrain, consisting of the epithalamus, thalamus (dorsal thalamus), hypothalamus, and ventral thalamus (subthalamus). See brain.... diencephalon
n. the structures, collectively, at the anterior end of the brainstem, comprising the *epithalamus, *thalamus, *hypothalamus, and subthalamus, all of which are concerned with the reception and processing of information that enters from sensory nerve pathways.... thalamencephalon
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