Dietrich Susanne, Hertrich Ingo, Müller-Dahlhaus Florian, Ackermann Hermann, Belardinelli Paolo, Desideri Debora, Seibold Verena C, Ziemann Ulf
Department of Neurology & Stroke, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
Department of Psychology, Evolutionary Cognition, University of Tübingen, Tübingen, Germany.
Front Neurosci. 2018 May 29;12:361. doi: 10.3389/fnins.2018.00361. eCollection 2018.
The pre-supplementary motor area (pre-SMA) is engaged in speech comprehension under difficult circumstances such as poor acoustic signal quality or time-critical conditions. Previous studies found that left pre-SMA is activated when subjects listen to accelerated speech. Here, the functional role of pre-SMA was tested for accelerated speech comprehension by inducing a transient "virtual lesion" using continuous theta-burst stimulation (cTBS). Participants were tested (1) prior to (pre-baseline), (2) 10 min after (test condition for the cTBS effect), and (3) 60 min after stimulation (post-baseline) using a sentence repetition task (formant-synthesized at rates of 8, 10, 12, 14, and 16 syllables/s). Speech comprehension was quantified by the percentage of correctly reproduced speech material. For high speech rates, subjects showed decreased performance after cTBS of pre-SMA. Regarding the error pattern, the number of incorrect words without any semantic or phonological similarity to the target context increased, while related words decreased. Thus, the transient impairment of pre-SMA seems to affect its inhibitory function that normally eliminates erroneous speech material prior to speaking or, in case of perception, prior to encoding into a semantically/pragmatically meaningful message.
补充运动前区（pre-SMA）在诸如声学信号质量差或时间紧迫等困难情况下参与言语理解。先前的研究发现，当受试者听加速语音时，左侧补充运动前区会被激活。在此，通过使用连续theta爆发刺激（cTBS）诱导短暂的“虚拟损伤”，测试了补充运动前区在加速言语理解中的功能作用。使用句子重复任务（以每秒8、10、12、14和16个音节的速率进行共振峰合成）对参与者进行了测试：（1）在刺激前（基线前），（2）刺激后10分钟（cTBS效应的测试条件），以及（3）刺激后60分钟（基线后）。通过正确再现言语材料的百分比来量化言语理解。对于高语速，补充运动前区经cTBS刺激后，受试者的表现下降。关于错误模式，与目标语境没有任何语义或语音相似性的错误单词数量增加，而相关单词数量减少。因此，补充运动前区的短暂损伤似乎会影响其抑制功能，该功能通常会在说话之前消除错误的言语材料，或者在感知情况下，在编码为语义/语用有意义的信息之前消除错误的言语材料。
