Li Chiang-shan Ray, Huang Cong, Constable R Todd, Sinha Rajita
Department of Psychiatry, Magnetic Resonance Research Center, Yale University, New Haven, Connecticut 06519, USA.
J Neurosci. 2006 Jan 4;26(1):186-92. doi: 10.1523/JNEUROSCI.3741-05.2006.
Execution of higher cortical functions requires inhibitory control to restrain habitual responses and meet changing task demands. We used functional magnetic resonance imaging to show the neural correlates of response inhibition during a stop-signal task. The task has a frequent "go" stimulus to set up a pre-potent response tendency and a less frequent "stop" signal for subjects to withhold their response. We contrasted brain activation between successful and failed inhibition for individual subjects and compared groups of subjects with short and long stop-signal reaction times. The two groups of subjects did not differ in their inhibition failure rates or the extent of signal monitoring, error monitoring, or task-associated frustration ratings. The results showed that short stop-signal reaction time or more efficient response inhibition was associated with greater activation in the superior medial and precentral frontal cortices. Moreover, activation of these inhibitory motor areas correlated negatively with stop-signal reaction time. These brain regions may represent the neural substrata of response inhibition independent of other cognitive and affective functions.
执行高级皮质功能需要抑制控制，以抑制习惯性反应并满足不断变化的任务需求。我们使用功能磁共振成像来显示停止信号任务期间反应抑制的神经关联。该任务有一个频繁出现的“执行”刺激，以建立一种优势反应倾向，以及一个较少出现的“停止”信号，让受试者抑制他们的反应。我们对比了个体受试者成功抑制和失败抑制之间的大脑激活情况，并比较了停止信号反应时间短和长的受试者组。两组受试者在抑制失败率、信号监测程度、错误监测或任务相关的挫折评分方面没有差异。结果表明，较短的停止信号反应时间或更有效的反应抑制与内侧上额叶皮质和中央前回皮质更大的激活相关。此外，这些抑制性运动区域的激活与停止信号反应时间呈负相关。这些脑区可能代表了独立于其他认知和情感功能的反应抑制的神经基础。
