Date of Award
Master of Science
Ann L. Smiley-oyen
It has been suggested that to make a goal-directed reach to grasp movement, precise visual information of target and hand is important. In spite of various studies relating to visual feedback in reach to grasp, few researchers have investigated the parameters of this behavior in relation to saccadic eye movement. Specifically, research in this area lacks insight about the contribution of visual feedback before and after the occurrence of saccadic eye movement. The purpose of this study was to investigate the influence of eye movement on the characteristics of the hand movement during a reach to grasp task. In this experiment, 9 college-age individuals performed the task of reaching and grasping a vertical dowel in two conditions: (1) with eye movement and (2) without eye movement (by fixating eye on central dowel). Further, we compared the performance in three sub-conditions: (1) full vision, (2) vision block before eye movement, and (3) vision block after eye movement. We found that presence or absence of either eye movement or continuous vision of target and hand does not modify the accuracy of grasp. Reach duration was shorter with full vision and reach trajectory was shorter when eye movement was coordinated with hand movement. We concluded that continuous vision of the hand and target is not necessary for the online control of these complex movements, but vision is necessary for optimizing the speed of the movement.
Ranjan, Sumit, "Relationship of eye and hand movements during perturbed reaching tasks" (2011). Graduate Theses and Dissertations. 12005.