Allen Greg, Müller Ralph-Axel, Courchesne Eric
Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Biol Psychiatry. 2004 Aug 15;56(4):269-78. doi: 10.1016/j.biopsych.2004.06.005.
The cerebellum is one of the most consistent sites of neuroanatomic abnormality in autism, yet it is still unclear how such pathology impacts cerebellar function. In normal subjects, we previously demonstrated with functional magnetic resonance imaging (fMRI) a dissociation between cerebellar regions involved in attention and those involved in a simple motor task, with motor activation localized to the anterior cerebellum ipsilateral to the moving hand. The purpose of the present investigation was to examine activation in the cerebella of autistic patients and normal control subjects performing this motor task.
We studied eight autistic patients and eight matched normal subjects, using fMRI. An anatomic region-of-interest approach was used, allowing a detailed examination of cerebellar function.
Autistic individuals showed significantly increased motor activation in the ipsilateral anterior cerebellar hemisphere relative to normal subjects, in addition to atypical activation in contralateral and posterior cerebellar regions. Moreover, increased activation was correlated with the degree of cerebellar structural abnormality.
These findings strongly suggest dysfunction of the autistic cerebellum that is a reflection of cerebellar anatomic abnormality. This neurofunctional deficit might be a key contributor to the development of certain diagnostic features of autism (e.g., impaired communication and social interaction, restricted interests, and stereotyped behaviors).
小脑是自闭症中神经解剖学异常最一致的部位之一，但目前仍不清楚这种病理状况如何影响小脑功能。在正常受试者中，我们之前通过功能磁共振成像（fMRI）证明，参与注意力的小脑区域与参与简单运动任务的小脑区域之间存在分离，运动激活定位于与运动手同侧的小脑前部。本研究的目的是检查执行此运动任务的自闭症患者和正常对照受试者小脑的激活情况。
我们使用fMRI研究了8名自闭症患者和8名匹配的正常受试者。采用解剖学感兴趣区域方法，以便详细检查小脑功能。
与正常受试者相比，自闭症个体同侧小脑前半球的运动激活显著增加，此外，对侧和小脑后部区域也有非典型激活。此外，激活增加与小脑结构异常程度相关。
这些发现强烈表明自闭症患者的小脑功能障碍反映了小脑解剖学异常。这种神经功能缺陷可能是自闭症某些诊断特征（如沟通和社交互动受损、兴趣受限和刻板行为）发展的关键因素。
