The effect of non-veridical perception for external time lag on intra-modal perception of self-generated stimuli (original) (raw)

Neuroscience Research, 2010

Abstract

An important issue in motor learning (or adaptation) is to reveal how our brain acquires the error information necessary to improve the task performance. The present study focuses on the effect (problem) of timing of the error feedback. It was reported that aftereffect of prism adaptation in manual reaching task was significantly reduced if the visual feedback of the endpoint was delayed more than 50 ms (Kitazawa et al. 1995). This suggests that error feedback is most effective when it was synchronized with the end of reaching movement. Here, we raise two questions to further elucidate the mechanism accepting error information. First, which is the decisive timing for error feedback, the end of body movement or the end of given task? Second, if the task end is essential, is any sensory cue required for knowing the timing? To answer these questions, we conducted a virtual shooting experiment where subjects adjusted his/her wrist movement to meet a target as accurately as possible. The timing of visual feedback of hit location was manipulated: synchronized with (±0 ms), delayed to (+250 ms and +500 ms), and ahead of (−250 ms) the actual hit timing. The time from throwing movement to target hit was also varied (250 ms or 500 ms) to examine the effect of the time from the movement end. When the error feedback was given either delayed or ahead, the amount of the aftereffect significantly diminished, irrelevant to the time from movement end. This means that the adaptation was most prominent when the error information was fed back at the task end (not at the movement end). The similar consequence was seen even when no sensory cue was given at the task end. These results suggest that our brain may predict the timing of task end and accepts error information synchronized with the predicted task end.

Takuya Honda hasn't uploaded this paper.

Let Takuya know you want this paper to be uploaded.

Ask for this paper to be uploaded.