Department of Rehabilitation for Sensory Functions, Research Institute, National Rehabilitation Center for Persons with Disabilities, 4-1 Namiki, Tokorozawa, Saitama, 359-8555, Japan.
Exp Brain Res. 2010 Jun;203(3):593-600. doi: 10.1007/s00221-010-2269-4. Epub 2010 May 8.
Stereotyped behaviors should be inhibited under some circumstances in order to encourage appropriate behavior. Psychiatrists have used the modified rock-paper-scissors (RPS) task to examine the inhibition of stereotyped behavior. When subjects are required to lose in response to a gesture, it is difficult for them to lose, and they have a tendency to win involuntarily. It is thought that the win response is the stereotyped response in the RPS task, and the difficulty in making positive attempts to lose is due to the requirement for inhibition of the stereotyped response. In this study, we investigated the brain regions related to inhibition of the stereotyped response using functional magnetic resonance imaging (fMRI). Subjects were assigned to one of two groups: the "win group" or the "lose group." The lose group showed higher activation of the left dorsolateral prefrontal cortex (DLFPC) when compared to the win group. We also delivered transcranial magnetic stimulation (TMS) while the subjects performed the modified RPS task to investigate whether the left DLPFC (middle frontal gyrus, Brodmann area, BA 9) was directly involved in the inhibition of the stereotyped response. When TMS was delivered before onset of the visual stimulus, the subjects displayed increased response errors. In particular, the subjects had a tendency to win erroneously in a lose condition even though they were required to lose. These results indicate involvement of the left DLPFC in inhibition of the stereotyped responses, which suggests that this region is associated with inhibition of the preparatory setting for stereotyped responses rather than inhibition of ongoing processing to produce a stereotyped response.
刻板行为应该在某些情况下受到抑制，以鼓励适当的行为。精神科医生使用改良的石头-剪刀-布（RPS）任务来检查刻板行为的抑制。当要求受试者根据手势输时，他们很难输，并且不由自主地倾向于赢。人们认为赢的反应是 RPS 任务中的刻板反应，而难以积极尝试输是由于抑制刻板反应的要求。在这项研究中，我们使用功能磁共振成像（fMRI）研究了与抑制刻板反应相关的大脑区域。受试者被分配到两个组之一：“赢组”或“输组”。与赢组相比，输组显示出左侧背外侧前额叶皮层（DLFPC）的更高激活。我们还在受试者执行改良的 RPS 任务时施加经颅磁刺激（TMS），以研究左侧 DLPFC（额中回，Brodmann 区，BA9）是否直接参与抑制刻板反应。当 TMS 在视觉刺激开始之前施加时，受试者的反应错误增加。特别是，即使要求受试者输，他们也倾向于错误地赢。这些结果表明左侧 DLPFC 参与了刻板反应的抑制，这表明该区域与抑制刻板反应的预备设置有关，而不是抑制产生刻板反应的正在进行的处理。
