Miller Luke E, Cawley-Bennett Andrew, Longo Matthew R, Saygin Ayse P
Department of Cognitive Science, University of California, San Diego, USA.
Kavli Institute for Brain and Mind, University of California, San Diego, USA.
Exp Brain Res. 2017 Oct;235(10):2917-2926. doi: 10.1007/s00221-017-5028-y. Epub 2017 Jul 12.
Two decades of research have demonstrated that using a tool modulates spatial representations of the body. Whether this embodiment is specific to representations of the tool-using limb or extends to representations of other body parts has received little attention. Several studies of other perceptual phenomena have found that modulations to the primary somatosensory representation of the hand transfers to the face, due in part to their close proximity in primary somatosensory cortex. In the present study, we investigated whether tool-induced recalibration of tactile perception on the hand transfers to the cheek. Participants verbally estimated the distance between two tactile points applied to either their hand or face, before and after using a hand-shaped tool. Tool use recalibrated tactile distance perception on the hand-in line with previous findings-but left perception on the cheek unchanged. This finding provides support for the idea that embodiment is body-part specific. Furthermore, it suggests that tool-induced perceptual recalibration occurs at a level of somatosensory processing, where representations of the hand and face have become functionally disentangled.
二十年的研究表明，使用工具会调节身体的空间表征。这种具身化是否特定于使用工具的肢体表征，还是会扩展到其他身体部位的表征，很少受到关注。几项关于其他感知现象的研究发现，对手的初级体感表征的调节会转移到面部，部分原因是它们在初级体感皮层中位置相近。在本研究中，我们调查了工具引起的手部触觉感知重新校准是否会转移到脸颊。参与者在使用手形工具前后，通过口头估计施加在他们手部或面部的两个触觉点之间的距离。使用工具会像之前的研究结果一样重新校准手部的触觉距离感知，但面部的感知保持不变。这一发现支持了具身化是特定于身体部位的观点。此外，它表明工具引起的感知重新校准发生在体感处理层面，在这个层面上手部和面部的表征在功能上已经分离。
