DYNAMICS OF ACCOMMODATIVE VERGENCE MOVEMENTS CONTROLLED BY THE DOMINANT AND NONDOMINANT EYE

Accommodative vergence responses to accommodative stimuli presented at three different amplitudes in a stepwise and a sinusoidal mode to eit her the dominant or the non-dominant eye were studied. The motor contr ol loop was opened by one eye viewing the target and the other eye cov ered. Each eye was stimulated monocularly and eye movements were recor ded with an infra-red reflection system. Latency and time constant of the accommodative vergence response to step stimulation or the phase o f the vergence response to sine wave stimulation, did not vary systema tically with stimulus amplitude or eye stimulated. However, the gain o f the accommodative vergence movements was highest in the non-dominant eye at a particular stimulus amplitude. This suggested that accommoda tive vergence angles can vary depending on which eye is leading and dr iving the accommodative vergence system in a specific fixation situati on.