Sensory and nonsensory portions of the nucleus “ventralis posterior” thalami of chimpanzee and man

Abstract
In man and chimpanzee, the large-celled region in the posteroinferior portion of the lateroventral thalamic mass, commonly called the nucleus ventralis posterior thalami, is separated cytoarchitecturally into two regions. The anterior portion is called the nucleus ventrointermedius (Vim) and the posterior part, the nucleus ventrocaudalis (Vc). In the chimpanzee it was found that most of the fibers from the superior cerebellar peduncle entered Vim on the way to distribution in the anterior half of the lateroventral thalamic mass. Fibers from the posterior spinal column (medial lemniscus) entered the Vc. No overlap was evident in the radiations from the two sources. An unusual human case is presented suporting the sensory function of Vc since a lesion in this nucleus resulted in persistent contralateral paresthesia. On the other side, a discrete lesion in Vim caused no sensory disturbance.
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