FROM MOVEMENT TO THOUGHT - ANATOMIC SUBSTRATES OF THE CEREBELLAR CONTRIBUTION TO COGNITIVE PROCESSING

The cerebellar contribution to cognitive operations and emotional beha vior is critically dependent upon the existence of plausible anatomic substrates. This paper explores these anatomic substrates, namely, the incorporation of the associative and paralimbic cerebral areas into t he cerebrocerebellar circuitry in nonhuman primates. Using the novel i nformation that has emerged concerning this system, proposed rules are derived and specific hypotheses offered concerning cerebellar functio n and the relationship between cerebellum and nonmotor behavior, as fo llow. (1) The associative and paralimbic incorporation into the cerebr ocerebellar circuit is the anatomic underpinning of the cerebellar con tribution to cognition and emotion. (2) There is topographic organizat ion of cognitive and behavioral functions within the cerebellum. The a rchicerebellum, vermis, and fastigial nucleus are principally concerne d with affective and autonomic regulation and emotionally relevant mem ory. The cerebellar hemispheres and dentate nucleus are concerned with executive, visual-spatial, language, and other mnemonic functions. (3 ) The convergence of inputs from multiple associative cerebral regions to common areas within the cerebellum facilitates cerebellar regulati on of supramodal functions. (4) The cerebellar contribution to cogniti on is one of modulation rather than generation. Dysmetria of (or ataxi c) thought and emotion are the clinical manifestations of a cerebellar lesion in the cognitive domain. (5) The cerebellum performs the same computations for associative and paralimbic functions as it does for t he sensorimotor system. These proposed rules and the general and speci fic hypotheses offered in this paper are testable using functional neu roimaging techniques. Neuroanatomy and functional neuroimaging may thu s be mutually advantageous in predicting and explaining new concepts o f cerebellar function. (C) 1996 Wiley-Liss, Inc.