DYNAMIC ASYMMETRIES IN DISPARITY CONVERGENCE EYE-MOVEMENTS

Vergence eye movements have traditionally been considered the product of a single neural control center and are usually studied by combining the movements of each eye into a single 'vergence' response. In the p resent experiment, disparity-driven eye movements were produced by sym metrical step stimuli, and the dynamic properties of each eye movement were analyzed separately. Although the final positions of the two eye s were symmetrical, large dynamic asymmetries often occurred. The timi ng between the two eyes showed fair synchrony as they attained maximum velocity at approximately the same time. Since the final static posit ions were symmetrical, asymmetries occurring during the initial dynami c component must necessarily be compensated by offsetting asymmetries in the latter portion or the response. (C) 1998 Elsevier Science Ltd. All rights reserved.