Shibuya Satoshi, Ohki Yukari
Department of Integrative Physiology, School of Medicine, Kyorin University, Tokyo, Japan.
Iperception. 2024 Dec 23;15(6):20416695241308146. doi: 10.1177/20416695241308146. eCollection 2024 Nov-Dec.
In the rubber hand illusion (RHI), individuals perceive a fake hand as their own if an unseen hand and a visible fake hand are stroked simultaneously. We examined how the RHI on either hand influenced the temporal order judgment (TOJ) of bimanual stimulation. In Experiment 1, participants performed TOJ during RHI or non-RHI conditions. When the fake hand was oriented in an anatomically incongruent position (non-RHI condition), the point of subjective simultaneity (PSS) from TOJ showed no difference between the stroke sides. However, during the RHI condition, the PSS tended to shift in the opposite direction to the stroke, resulting in a significant difference between the sides. This implies slower tactile processing in the illusion-affected hand. When participants performed an identical TOJ while watching the fake hand without stroking (Experiment 2), no PSS modulation was found. Our findings suggest the possibility that the RHI attenuates tactile processing, but its magnitude is small.
在橡皮手错觉（RHI）中，如果一只未被看到的手和一只可见的假手同时受到抚摸，个体就会将假手视为自己的手。我们研究了任一只手上的橡皮手错觉如何影响双手刺激的时间顺序判断（TOJ）。在实验1中，参与者在橡皮手错觉或非橡皮手错觉条件下进行时间顺序判断。当假手处于解剖学上不一致的位置时（非橡皮手错觉条件），时间顺序判断得出的主观同时性点（PSS）在抚摸的两侧之间没有差异。然而，在橡皮手错觉条件下，主观同时性点倾向于向与抚摸相反的方向偏移，导致两侧之间存在显著差异。这意味着受错觉影响的那只手的触觉处理较慢。当参与者在不抚摸的情况下观看假手时执行相同的时间顺序判断时（实验2），未发现主观同时性点的调制。我们的研究结果表明，橡皮手错觉有可能会减弱触觉处理，但程度较小。
