Modulation of auditory activity occurs before and during voluntary speech movement. However, it is unknown whether orofacial somatosensory input is modulated in the same manner. The current study examined whether or not the somatosensory event-related potentials (ERPs) in response to facial skin stretch are changed during speech and nonspeech production tasks. Specifically, we compared ERP changes to somatosensory stimulation for different orofacial postures and speech utterances. Participants produced three different vowel sounds (voicing) or non-speech oral tasks in which participants maintained a similar posture without voicing. ERP's were recorded from 64 scalp sites in response to the somatosensory stimulation under six task conditions (three vowels × voicing/posture) and compared to a resting baseline condition. The first negative peak for the vowel /u/ was reliably reduced from the baseline in both the voicing and posturing tasks, but the other conditions did not differ. The second positive peak was reduced for all voicing tasks compared to the posturing tasks. The results suggest that the sensitivity of somatosensory ERP to facial skin deformation is modulated by the task and that somatosensory processing during speaking may be modulated differently relative to phonetic identity.

中文翻译：

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语音产生过程中口面部体感衰减的变化。

听觉活动的调节发生在自愿性言语运动之前和之中。然而，未知是否以相同方式调制了面部的体感输入。当前的研究检查了在言语和非言语产生任务中，响应于面部皮肤拉伸的体感事件相关电位（ERP）是否发生了变化。具体来说，我们比较了针对不同口脸姿势和语音表达的ERP更改与体感刺激的比较。参与者产生了三种不同的元音（发声）或非语音口头任务，参与者保持相似的姿势而没有发声。在六个任务条件下（三个元音×发声/姿势），根据体感刺激从64个头皮部位记录了ERP，并将其与静止基线条件进行了比较。元音/ u /的第一个负峰值在发声和摆姿势任务中均已可靠地从基线降低，但其他条件没有变化。与姿势任务相比，所有发声任务的第二个正峰值都减小了。结果表明，该任务调节了体感ERP对面部皮肤变形的敏感性，并且在说话期间的体感处理可能相对于语音识别方式有所不同。