PDF(Pubmed)
Abstract：
Hearing one\'s own speech allows for acoustic self-monitoring in real time. Left-hemisphere motor planning regions are thought to give rise to efferent predictions that can be compared to true feedback in sensory cortices, resulting in neural suppression commensurate with the degree of overlap between predicted and actual sensations. Sensory prediction errors thus serve as a possible mechanism of detection of deviant speech sounds, which can then feed back into corrective action, allowing for online control of speech acoustics. The goal of this study was to assess the integrity of this detection-correction circuit in persons with aphasia (PWA) whose left-hemisphere lesions may limit their ability to control variability in speech output. We recorded magnetoencephalography (MEG) while 15 PWA and age-matched controls spoke monosyllabic words and listened to playback of their utterances. From this, we measured speaking-induced suppression of the M100 neural response and related it to lesion profiles and speech behavior. Both speaking-induced suppression and cortical sensitivity to deviance were preserved at the group level in PWA. PWA with more spared tissue in pars opercularis had greater left-hemisphere neural suppression and greater behavioral correction of acoustically deviant pronunciations, whereas sparing of superior temporal gyrus was not related to neural suppression or acoustic behavior. In turn, PWA who made greater corrections had fewer overt speech errors in the MEG task. Thus, the motor planning regions that generate the efferent prediction are integral to performing corrections when that prediction is violated.
摘要：
听到自己的语音可以实时进行声学自我监控。左半球运动规划区域被认为会产生传出预测，可以与感觉皮层中的真实反馈进行比较，导致神经抑制与预测和实际感觉之间的重叠程度相称。因此，感觉预测误差可作为检测异常语音的可能机制，然后可以反馈到纠正措施中，允许在线控制语音声学。这项研究的目的是评估失语症（PWA）患者的检测校正回路的完整性，这些患者的左半球病变可能会限制他们控制语音输出变异性的能力。我们记录了脑磁图（MEG），而15个PWA和年龄匹配的控件讲单音节单词并聆听其话语的回放。由此,我们测量了说话诱导的M100神经反应抑制，并将其与病变轮廓和言语行为相关联。在PWA中，说话诱导的抑制和皮层对偏差的敏感性均保持在组水平。pwa中保留更多组织的pwa具有更大的左半球神经抑制和更大的声学异常发音的行为校正，而颞上回的保留与神经抑制或声学行为无关。反过来,进行较大更正的PWA在MEG任务中的明显语音错误较少。因此，当违反该预测时,生成传出预测的运动规划区域对于执行校正是不可或缺的。
