Silas Weir Mitchell on the Cerebellum: Rich Neurophysiological Concepts and a Modern Perspective.

Silas Weir Mitchell (1829 - 1914), the Philadelphia-based neurologist, is considered a founding father of American neurology. Mitchell's 1869 paper on the physiology of the cerebellum is rich in both content and physiological concepts. Although several of the specific models proposed by Mitchell are no longer considered valid, a number of concepts, or collateral aspects of these concepts, are still considered of value today. No longer valid concepts are (1) that the cerebellum works in concert with the "spinal ganglia" to coordinate motion, and (2) that the cerebellum has a higher-order inhibitory effect on the "spinal ganglia." The valid concepts are (1) that the cerebellum is part of an integrated system of brain regions that produce and modulate movement, (2) that compensatory neural plasticity and cerebellar reserve allow the cerebellum to compensate in the setting of tissue damage, (3) that higher brain systems exert an inhibitory effect on lower brain systems, and (4) that there is a physiological gap between higher and lower life forms. This paper reviews these concepts.