ARM NERVE-CONDUCTION VELOCITY (NCV), BRAIN NCV, REACTION-TIME, AND INTELLIGENCE

Two hundred California students, 18 to 25 years old, were tested for nerve conduction velocity (NCV) in the arm and in the visual pathway of the brain, simple and choice reaction times, and Raven's Progressive Matrices test for nonverbal intelligence. Contrary to a prediction based on theoretical grounds, and also to one study, arm NCV did not correlate with this intelligence measure. It also did not correlate consistently with the brain NCVs or with reaction time. In contrast, these brain NCVs do correlate positively (as predicted) with this measure of intelligence in this group of subjects and also in each of five electrophysiological studies of mentally retarded or demented subjects (relative to normal controls). A correct interpretation of these results should assist our understanding of the neurophysiological basis for human information processing and intelligence. © 1991.