PROCESSES CONTROLLING VISUALLY EVOKED MOVEMENTS

The experiments described here are addressed at identifying some of the processes underlying arm and head movements in monkeys. We have indicated that these movements depend, at least partially, upon a process that specifies an equilibrium point between agonist and antagonist muscles rather than amplitude and duration of movement. In addition, our findings suggest that a major role of the feedback system is in updating and adjusting the execution of learned motor patterns when posture is changed. Compensation for unexpected disturbances occurring during a preprogrammed movement was not found to be a major function of afferent feedback. © 1979.