Abstract
Subjects fixating a target light attached to their stationary hand saw it move when illusory motion of their arm was induced by muscle vibration. During the experienced visual motion and change in visual direction of the target light, their eyes maintained steady fixation. The existence of an ‘oculobrachial ilusion’ provides evidence that visual direction depends on the operation of a spatial constancy mechanism interrelating sensory information about the external environment and the moment-to-moment postural configuration of the body.