Kammers Marjolein P M, Verhagen Lennart, Dijkerman H Chris, Hogendoorn Hinze, De Vignemont Frederique, Schutter Dennis J L G
Helmholtz Institute, Experimental Psychology, Utrecht University, Utrecht, The Netherlands.
J Cogn Neurosci. 2009 Jul;21(7):1311-20. doi: 10.1162/jocn.2009.21095.
In the rubber hand illusion (RHI), participants incorporate a rubber hand into a mental representation of one's body. This deceptive feeling of ownership is accompanied by recalibration of the perceived position of the participant's real hand toward the rubber hand. Neuroimaging data suggest involvement of the posterior parietal lobule during induction of the RHI, when recalibration of the real hand toward the rubber hand takes place. Here, we used off-line low-frequency repetitive transcranial magnetic stimulation (rTMS) in a double-blind, sham-controlled within-subjects design to investigate the role of the inferior posterior parietal lobule (IPL) in establishing the RHI directly. Results showed that rTMS over the IPL attenuated the strength of the RHI for immediate perceptual body judgments only. In contrast, delayed perceptual responses were unaffected. Furthermore, ballistic action responses as well as subjective self-reports of feeling of ownership over the rubber hand remained unaffected by rTMS over the IPL. These findings are in line with previous research showing that the RHI can be broken down into dissociable bodily sensations. The illusion does not merely affect the embodiment of the rubber hand but also influences the experience and localization of one's own hand in an independent manner. Finally, the present findings concur with a multicomponent model of somatosensory body representations, wherein the IPL plays a pivotal role in subserving perceptual body judgments, but not actions or higher-order affective bodily judgments.
在橡皮手错觉（RHI）中，参与者会将一只橡皮手纳入对自身身体的心理表征中。这种具有欺骗性的所有权感觉伴随着参与者真实手部的感知位置向橡皮手的重新校准。神经成像数据表明，在RHI诱导期间，当真实手部向橡皮手进行重新校准时，顶叶后小叶会参与其中。在此，我们采用离线低频重复经颅磁刺激（rTMS），通过双盲、假对照的被试内设计，直接研究顶叶后下部小叶（IPL）在建立RHI中的作用。结果显示，IPL部位的rTMS仅减弱了即时感知身体判断的RHI强度。相比之下，延迟的感知反应未受影响。此外，弹道动作反应以及对橡皮手所有权感觉的主观自我报告也未受IPL部位rTMS的影响。这些发现与先前的研究一致，即RHI可分解为可分离的身体感觉。这种错觉不仅影响橡皮手的身体化，还以独立的方式影响自身手部的体验和定位。最后，本研究结果与体感身体表征的多成分模型相符，其中IPL在支持感知身体判断方面起关键作用，但在动作或更高层次的情感身体判断方面并非如此。
