自闭症在静息态功能性连接上的研究进展

A Review on Resting State Functional Connectivity Studies in Autism Spectrum Disorder

摘要: 近年来自闭症发病率持续增加，对自身、家庭以及社会都有着消极影响。基于脑成像的静息态功能性连接研究对自闭症早期及客观诊断有着重要意义。与正常人相比，自闭症患者在静息态下长程和短程功能连接都可能存在差异，但不同研究的结果不一致。本文从短程和长程连接的定义、计算方式、脑成像仪器以及异常脑区等方面，总结自闭症静息态功能性连接研究的最新发现。这些发现不支持过往提出自闭症短程功能连接过度的理论假设，如在扣带回处自闭症青少年短程功能性连接不足。而在长程功能性连接，自闭症儿童半球间颞–颞连接及额区与其他区域间功能连接不足。因此在未来的研究中，探索在自闭症群体中呈现一致性变化的功能连接性，可以为基于脑成像的客观早期诊断提供依据。

Abstract: In recent year, the prevalence of autism spectrum disorder (ASD) increases rapidly, bringing about negative impacts on individuals with ASD, their families and the society. To date, a variety of Neuroimaging studies have revealed that altered resting state functional connectivity (RSFC) in either long-range or short-range is likely to be associated with ASD, which may potentially provide neuroimaging-based biomarker for early and objective diagnosis on ASD. However, the reported alterations in RSFC in ASD are not consistent across different studies. To clarify this inconsistency, we review the latest findings in the altered RSFC in ASD from various aspects, including the definition of short-range and long-range, analysis methods, brain imaging equipments, and abnormal brain regions. Not all evidence supports the prevailing hypothesis that individuals with ASD have short-range over-connectivity, for example, teenagers with ASD show weaker short-range RSFC in cingulate cortex. Nevertheless, these findings show consistently that individuals with ASD have long-range under-connectivity between the bilateral temporal lobes, and between the frontal cortex and others brain regions. Therefore, to identify RSFC on which individuals with ASD show consistent alteration is important for early and objective prediction of ASD.