Department of Psychology, City University London, EC1V 0HB, London, United Kingdom, and Department of Psychology, Complutense University of Madrid, 28223, Madrid, Spain.
J Neurosci. 2014 Feb 26;34(9):3263-7. doi: 10.1523/JNEUROSCI.0106-13.2014.
Current models of face perception propose that initial visual processing is followed by activation of nonvisual somatosensory areas that contributes to emotion recognition. To test whether there is a pure and independent involvement of somatosensory cortex (SCx) during face processing over and above visual responses, we directly measured participants' somatosensory-evoked activity by tactually probing (105 ms postvisual facial stimuli) the state of SCx during an emotion discrimination task while controlling for visual effects. Discrimination of emotional versus neutral expressions enhanced early somatosensory-evoked activity between 40 and 80 ms after stimulus onset, suggesting visual emotion processing in SCx. This effect was source localized within primary, secondary, and associative somatosensory cortex. Emotional face processing influenced somatosensory responses to both face (congruent body part) and finger (control site) tactile stimulation, suggesting a general process that includes nonfacial cortical representations. Gender discrimination of the same facial expressions did not modulate somatosensory-evoked activity. We provide novel evidence that SCx activation is not a byproduct of visual processing but is independently shaped by face emotion processing.
当前的面部感知模型提出，初始视觉处理之后会激活非视觉体感区域，这有助于情绪识别。为了测试在视觉反应之外，体感皮层（SCx）在面部处理过程中是否存在纯粹和独立的参与，我们通过在视觉面部刺激后 105 毫秒时触觉探测（直接测量参与者的体感诱发活动），在控制视觉效果的情况下，在进行情绪辨别任务期间测量 SCx 的状态。与中性表情相比，情绪表情的辨别增强了刺激开始后 40 到 80 毫秒之间的早期体感诱发活动，这表明 SCx 中的视觉情绪处理。这种效果在初级、次级和联合体感皮层内进行了源定位。对面部（一致的身体部位）和手指（对照部位）触觉刺激的体感反应受到情绪面部处理的影响，这表明存在包括非面部皮质代表的一般过程。对相同面部表情的性别辨别不会调节体感诱发活动。我们提供了新的证据表明，SCx 的激活不是视觉处理的副产品，而是独立地由面部情绪处理塑造的。
