Aging effects of changing fixation in a depth direction

Abstract

To investigate the effect of aging on vergence eye movement, we measured changes in the binocular eye movement of subjects when fixation points are changed from far/near or from near/far in symmetric vergence and asymmetric vergence. There tended to be increases in latency, time constants and the number of saccades and decreases in convergence angle changes in the young (below 10 years old) and aged (over 60 years old) subjects. These results suggest that young subjects do not have a completely developed vergence controlling mechanism, and the performance of this mechanism decreases in aged subjects.