Abstract
Various devices have been developed to enable humans to control remote objects using active hand movements. However, it is still unclear how the visual characteristics of a synchronously moving object influences hand movements. This study investigates the effects of visual appearance and orientation of a hand-controlled object on hand movements using a novel visuomotor task. The motion of a visual image on a monitor reflected the participants’ right hand movements in the forwards-backwards direction, but not in the lateral direction (i.e., the lateral position of the image was fixed). Participants performed continuous goal-directed back and forth movements of the visual image for one minute. The image’s appearance (hand and arrow) and orientation (forward (FW), leftward (LW), and rightward (RW)) were manipulated. Unconscious lateral deviations (i.e., drift movements) of the participant’s hand during the task were evaluated. Regardless of appearance, the leftward and rightward image induced leftward and rightward drift movements, compared to the forward image. However, the modulation sizes were similar using arrow images, but not using hand images. Specifically, anatomically plausible hand images elicited greater drift movements than anatomically implausible images. This suggests that both orientation and appearance of a hand-controlled object influences hand movements according to stimulus-response compatibility and body-representation changes.