ABSTRACT

Postural movements can be controlled so as to facilitate visual performance. This chapter examines whether eye movements might influence body sway. Oblak, Gregoric, & Gyergyek (1985) found that body sway was reduced during visual tracking, relative to sway during fixation. This suggests that body sway may be modulated to facilitate changes in the direction of gaze. It is predicted that sway amplitude would be reduced only during visually guided eye movements; would correlate negatively with the frequency of eye movements. In two experiments (respectively fourteen and twelve subjects), subjects stood barefoot with their feet together. Body sway was reduced in the two axes for both head and torso when subjects used eye movements to track moving targets (relative to fixation of a stationary target) but only when eye movements were visually guided. Thus, reductions in postural movement can be attributed to the control of gaze, rather than to movement of the eyes as such.