Ning Ning, Peng Danling, Liu Xiangping, Yang Shuang
School of Education, Soochow University, Suzhou, Jiang Su, China.
State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China.
PLoS One. 2017 Jan 9;12(1):e0168836. doi: 10.1371/journal.pone.0168836. eCollection 2017.
The aim of the present study was to investigate the speech preparation processes of adults who stutter (AWS). Fifteen AWS and fifteen adults with fluent speech (AFS) participated in the experiment. The event-related potentials (ERPs) were recorded in a foreperiod paradigm. The warning signal (S1) was a color square, and the following imperative stimulus (S2) was either a white square (the Go signal that required participants to name the color of S1) or a white dot (the NoGo signal that prevents participants from speaking). Three differences were found between AWS and AFS. First, the mean amplitude of the ERP component parietal positivity elicited by S1 (S1-P3) was smaller in AWS than in AFS, which implies that AWS may have deficits in investing working memory on phonological programming. Second, the topographic shift from the early phase to the late phase of contingent negative variation occurred earlier for AWS than for AFS, thus suggesting that the motor preparation process is promoted in AWS. Third, the NoGo effect in the ERP component parietal positivity elicited by S2 (S2-P3) was larger for AFS than for AWS, indicating that AWS have difficulties in inhibiting a planned speech response. These results provide a full picture of the speech preparation and response inhibition processes of AWS. The relationship among these three findings is discussed. However, as stuttering was not manipulated in this study, it is still unclear whether the effects are the causes or the results of stuttering. Further studies are suggested to explore the relationship between stuttering and the effects found in the present study.
本研究的目的是调查口吃成年人（AWS）的言语准备过程。15名口吃成年人和15名言语流畅的成年人（AFS）参与了该实验。在预备期范式中记录事件相关电位（ERP）。警告信号（S1）是一个彩色方块，随后的命令刺激（S2）要么是一个白色方块（要求参与者说出S1颜色的执行信号），要么是一个白色圆点（阻止参与者说话的禁止信号）。在口吃成年人和言语流畅的成年人之间发现了三个差异。首先，S1引发的ERP成分顶叶正波（S1-P3）的平均振幅在口吃成年人中比在言语流畅的成年人中更小，这意味着口吃成年人在将工作记忆投入到语音编程方面可能存在缺陷。其次，依存性负变从早期到晚期的地形变化在口吃成年人中比在言语流畅的成年人中出现得更早，因此表明口吃成年人的运动准备过程得到了促进。第三，S2引发的ERP成分顶叶正波（S2-P3）中的禁止效应在言语流畅的成年人中比在口吃成年人中更大，表明口吃成年人在抑制计划好的言语反应方面存在困难。这些结果全面呈现了口吃成年人的言语准备和反应抑制过程。讨论了这三个发现之间的关系。然而，由于本研究中未对口吃进行操控，目前仍不清楚这些效应是口吃的原因还是结果。建议进一步开展研究以探索口吃与本研究中发现的效应之间 的关系。
