ABSTRACT

Several adult studies have proved the existence of a shared neural circuit in the somatosensory cortices that responds to both the body being touched and the sight of the body being touched. Despite the fundamental role of touch in infancy, the existence of similar visuo-tactile mirroring processes, supporting both felt and seen touch, still needs an in-depth empirical investigation. To this aim, we explored 8-month-olds mu desynchronization over somatosensory sites in response to felt and observed touch in a live experimental setting. EEG desynchronization (6–8 Hz mu frequency range) was measured during three experimental conditions: i) infants were stroked on their right hand by a parent (Touch condition); ii) infants observed a right hand being stroked (Observation Touch condition); iii) infants observed a right hand moving over the left hand without making contact (Action Control condition). Mu desynchronization of somatosensory sites contralateral to the hand being stroked emerged in response to both Touch and Observation Touch conditions, but not in the Action control condition. Further, greater mu desynchronization was found in the Touch and Observation Touch conditions as compared to the Action control condition. Our results highlight the early involvement of a shared somatosensory system, likely supporting infants’ understanding of others’ tactile sensations.

摘要

几项成人研究已经证明，躯体感觉皮层中存在一个共享的神经回路，它对被触摸的身体和被触摸的身体的视线做出反应。尽管触觉在婴儿期具有基本作用，但支持感觉和视觉触觉的类似视觉触觉镜像过程的存在仍然需要深入的实证研究。为此，我们在现场实验环境中探索了 8 个月大的儿童在体感部位对感觉和观察到的触摸的反应。在三个实验条件下测量 EEG 不同步（6-8 Hz mu 频率范围）：i）婴儿被父母抚摸右手（触摸条件）；ii) 婴儿观察到右手被抚摸（观察触摸条件）；iii) 婴儿观察到右手在左手上方移动而不接触（动作控制条件）。与被抚摸的手对侧的体感部位的 Mu 不同步出现在触摸和观察触摸条件下，但不是在动作控制条件下。此外，与 Action 控制条件相比，在 Touch 和 Observation Touch 条件中发现了更大的 mu 不同步。我们的结果突出了共享体感系统的早期参与，这可能支持婴儿对他人触觉的理解。与 Action 控制条件相比，在 Touch 和 Observation Touch 条件中发现了更大的 mu 不同步。我们的结果突出了共享体感系统的早期参与，这可能支持婴儿对他人触觉的理解。与 Action 控制条件相比，在 Touch 和 Observation Touch 条件中发现了更大的 mu 不同步。我们的结果突出了共享体感系统的早期参与，这可能支持婴儿对他人触觉的理解。