1994 Volume 78 Issue 10 Pages 545-554
The behavior of gaze in the task of color matching was studied at various stimuli separations from 6 to 120 deg. for two subjects. Eye and head positions were measured with a limbus tracker and a CCD camera attached to a pair of spectacles. Whereas the time required per match was almost constant, the number of gaze shifts decreased and the fixational duration increased with stimuli separation. This indicates a change in the strategy in the visual system. For one subject, head rotation started at 30 deg. separation and for the other at 15 deg. separation. Whenever the subjects' head rotated, vestibulo-ocular reflex (VOR) occurred after eye saccade. Moreover, at 60deg. separation or more, pre-saccade VOR and multiple saccades were observed. The time duration for gaze shifting increased with stimuli separation, but at larger separation angles the slope of the time duration increase curve became gentler.