Centre for Brain Science, Department of Psychology, University of Essex, Colchester, CO4 3SQ, UK.
Department of Psychology, Goldsmiths, University of London, New Cross, London, SE14 6NW, UK; School of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
Biol Psychol. 2019 Sep;146:107719. doi: 10.1016/j.biopsycho.2019.107719. Epub 2019 Jun 14.
Observing others being touched activates similar brain areas as those activated when one experiences a touch oneself. Event-related potential (ERP) studies have revealed that modulation of somatosensory components by observed touch occurs within 100 ms after stimulus onset, and such vicarious effects have been taken as evidence for empathy for others' tactile experiences. In previous studies body parts have been presented from a first person perspective. This raises the question of the extent to which somatosensory activation by observed touch to body parts depends on the perspective from which the body part is observed. In this study (N = 18), we examined the modulation of somatosensory ERPs by observed touch delivered to another person's hand when viewed as if from a first person versus a third person perspective. We found that vicarious touch effects primarily consist of two separable components in the early stages of somatosensory processing: an anatomical mapping for touch in first person perspective at P45, and a specular (mirror like) mapping for touch in third person perspective at P100. This is consistent with suggestions that vicarious representations exist to support predictions for one's own bodily events, but also to enable predictions of a social or interpersonal kind, at distinct temporal stages.
观察他人被触碰会激活与自身被触碰时相同的大脑区域。事件相关电位 (ERP) 研究表明，观察到的触碰对体感成分的调制发生在刺激开始后 100 毫秒内，这种替代效应被认为是对他人触觉体验产生共鸣的证据。在之前的研究中，身体部位是从第一人称视角呈现的。这就提出了一个问题，即观察到的身体部位的触碰所引起的体感激活在多大程度上取决于观察身体部位的视角。在这项研究中（N=18），我们研究了当以第一人称视角而非第三人称视角观察到另一个人的手被触碰时，体感 ERP 被观察到的触碰所调制的情况。我们发现，替代性触碰效应主要由体感加工早期的两个可分离成分组成：在 P45 处对第一人称视角中的触碰进行解剖映射，在 P100 处对第三人称视角中的触碰进行镜像映射。这与替代性代表存在以支持对自身身体事件的预测，但也以不同的时间阶段支持对社会或人际类型的预测的观点一致。
