在2008年2月7日的《神经元》(Neuron)上,Chiu等人研究了社交活动中的自闭症病人的神经活动。大脑控制部分显示出一种神经反应模式,该模式可以区分出个体在人际交往中表现出的行为,哪些是自己的决定,哪些是他人的意愿。
我们知道,从事社交活动的关键是人们可以对自身与他人的意愿做出正确的行为反应。自闭症病人在人际交流过程中不能做出恰当地行为反应,从而导致与人际交往困难。最值得注意的是,自闭症患者表现出严重的失去“自我”的反应模式特征,这种特征参数与自闭症的严重性相关,因此能够客观地描述症状的严重程度。
在最新研究中,Chiu等人采用两个独立的脑功能核磁共振成像系统研究了自闭症男性患者的神经活动。首先,他们从影像中提取了大脑控制部分的扣带皮层反应的基本单位,其中大脑控制部分反映了人的想象与特征向量(自振)结合而产生的特定执行行为。其次,他们发现,在人际交往中,个体自己作出决定(自我阶段)时会也引起同样的自振过程。最后,通过人与人之间的交流游戏,研究人员发现,当人们与同伴交流时,男性自闭症病人表现出扣带皮层自我反应的急剧减少,减少的程度在变化参数上与病人症状的严重程度有关,说明扣带皮层自我反应的减少值可以客观地反映神经的“内在表型”。
这项研究成果可能为定量评估自闭症提供参考方法。(科学网 武彦文/编译)
生物谷推荐原始出处:
(Neuron),Vol 57, 463-473, 07 February 2008,Pearl H. Chiu, P. Read Montague
Self Responses along Cingulate Cortex Reveal Quantitative Neural Phenotype for High-Functioning Autism
Pearl H. Chiu, M. Amin Kayali, Kenneth T. Kishida, Damon Tomlin, Laura G. Klinger, Mark R. Klinger, and P. Read Montague,
Summary
Attributing behavioral outcomes correctly to oneself or to other agents is essential for all productive social exchange. We approach this issue in high-functioning males with autism spectrum disorder (ASD) using two separate fMRI paradigms. First, using a visual imagery task, we extract a basis set for responses along the cingulate cortex of control subjects that reveals an agent-specific eigenvector (self eigenmode) associated with imagining oneself executing a specific motor act. Second, we show that the same self eigenmode arises during one's own decision (the self phase) in an interpersonal exchange game (iterated trust game). Third, using this exchange game, we show that ASD males exhibit a severely diminished cingulate self response when playing the game with a human partner. This diminishment covaries parametrically with their behaviorally assessed symptom severity, suggesting its value as an objective endophenotype. These findings may provide a quantitative assessment tool for high-functioning ASD.