Abstract
This study investigated the effects of rotation and delay of visual feedback on self-body movement recognition. In the present experiment, visual feedback of subject's hand movement was delayed by hundreds of milliseconds and rotated by 0-270°(at 90° intervals). The subject was required to judge the temporal discrepancy between the hand movement and its visual feedback in a forced-choice manner. In one group the subject was instructed to move their own hand at the experimenter's instruction (active movement), while in another group the subject's hand was moved by the experimenter (passive movement). The results showed that the delay detection rate was increased as the delay length becomes larger both in active and passive movements. Statistical analyses revealed that rotation of visual feedback has an effect to elongate the delay detection threshold (50% detection rate), and the threshold was significantly longer in the 180° rotation condition than in the 0° rotation condition. The steepness of delay detection curve was significantly steeper in active than passive movement. However, there was no significant interaction between rotation and movement (active ⁄ passive) factors. We suppose independent effects of rotation and delay of visual feedback on self-body recognition.
