抑制控制在言語產生中起重要作用,其功能異常可能是造成口吃的原因之一。前人研究發現成年口吃者存在與抑制控制相關的腦區(右側額下回)的過度激活,但在口吃兒童中沒有。此外,關于口吃兒童抑制控制的行為研究只運用了按鍵任務,結果也存在很大爭議。故本研究運用出聲Go/Nogo任務檢驗口吃兒童在言語產生中的反應抑制能力。結果發現,口吃組與對照組在擊中和虛報的反應時、漏報率和虛報率上均未表現出組間差異,而且口吃組的這些指標與口吃程度也沒有顯著相關。在排除速度與準確率的權衡后,上述結果支持口吃兒童在言語產生中對發音運動的反應抑制并不存在普遍缺陷,在一定程度上支持了成年口吃者右側額下回過度激活的補償解釋。

Inhibitory control plays an important role in speech production, and its dysfunction may be one of the causes of stuttering.Previous studies have found that adults who stutter(AWS) have over-activation in the right inferior frontal gyrus, which is associated with inhibitory control, but not in the children who stutter(CWS). In addition, the previous researches on inhibitory control of CWS only involve the response of pressing buttons. These results are also controversial. Therefore, this study used the verbal Go/Nogo task to test the ability of inhibitory control of CWS in speech production. The results showed that there is no significant difference in reaction times of hit and false alarms, and percentages of miss trials and false alarms between the CWS and the control group. There is also no correlation between these indicators and the degree of stuttering for the CWS group. Ruling out the speed-accuracy tradeoff, these results suggest the deficit in the inhibitory control of speech production is not universal for the CWS. This supports the speculation to some extent that the right inferior frontal gyrus of AWS is over-activated to compensate for the inadequate activation of the contralateral language area.