Daliri Ayoub, Max Ludo
University of Washington, Seattle, WA, United States; Now at Boston University, Boston, MA, United States.
University of Washington, Seattle, WA, United States; Haskins Laboratories, New Haven, CT, United States.
Brain Lang. 2015 Apr;143:59-68. doi: 10.1016/j.bandl.2015.03.002. Epub 2015 Mar 18.
Stuttering is associated with atypical structural and functional connectivity in sensorimotor brain areas, in particular premotor, motor, and auditory regions. It remains unknown, however, which specific mechanisms of speech planning and execution are affected by these neurological abnormalities. To investigate pre-movement sensory modulation, we recorded 12 stuttering and 12 nonstuttering adults' auditory evoked potentials in response to probe tones presented prior to speech onset in a delayed-response speaking condition vs. no-speaking control conditions (silent reading; seeing nonlinguistic symbols). Findings indicate that, during speech movement planning, the nonstuttering group showed a statistically significant modulation of auditory processing (reduced N1 amplitude) that was not observed in the stuttering group. Thus, the obtained results provide electrophysiological evidence in support of the hypothesis that stuttering is associated with deficiencies in modulating the cortical auditory system during speech movement planning. This specific sensorimotor integration deficiency may contribute to inefficient feedback monitoring and, consequently, speech dysfluencies.
口吃与感觉运动脑区（特别是前运动区、运动区和听觉区）的非典型结构和功能连接有关。然而，尚不清楚这些神经学异常会影响言语计划和执行的哪些具体机制。为了研究运动前的感觉调制，我们记录了12名口吃成年人和12名非口吃成年人在延迟反应说话条件下（与不说话对照条件：默读；看非语言符号）言语开始前呈现探测音时的听觉诱发电位。研究结果表明，在言语运动计划过程中，非口吃组表现出听觉处理的统计学显著调制（N1波幅降低），而口吃组未观察到这种情况。因此，获得的结果提供了电生理学证据，支持口吃与言语运动计划过程中调节皮质听觉系统的缺陷有关这一假设。这种特定的感觉运动整合缺陷可能导致反馈监测效率低下，进而导致言语不流畅。
