Child Neuroscience Laboratory, Child Study Center, Yale School of Medicine, 230 South Frontage Road, New Haven, CT 06519, USA.
Behav Brain Res. 2013 Aug 15;251:163-7. doi: 10.1016/j.bbr.2013.04.021. Epub 2013 Apr 22.
Research has demonstrated the potential role of the brainstem in the pathobiology of autism. Previous studies have suggested reductions in brainstem volume and a relationship between this structure and sensory abnormalities. However, little is known regarding the developmental aspects of the brainstem across childhood and adolescence. The goal of this pilot study was to examine brainstem development via MRI volumetry using a longitudinal research design. Participants included 23 boys with autism and 23 matched controls (age range=8-17 years), all without intellectual disability. Participants underwent structural MRI scans once at baseline and again at two-year follow-up. Brainstem volumetric measurements were performed using the BRAINS2 software package. There were no significant group differences in age, gender, handedness, and total brain volume; however, full-scale IQ was higher in controls. Autism and control groups showed different patterns of growth in brainstem volume. While whole brainstem volume remained stable in controls over the two-year period, the autism group showed increases with age reaching volumes comparable to controls by age 15 years. This increase of whole brainstem volume was primarily driven by bilateral increases in gray matter volume. Findings from this preliminary study are suggestive of developmental brainstem abnormalities in autism primarily involving gray matter structures. These findings are consistent with autism being conceptualized as a neurodevelopmental disorder with alterations in brain-growth trajectories. More longitudinal MRI studies are needed integrating longitudinal cognitive/behavioral data to confirm and elucidate the clinical significance of these atypical growth patterns.
研究已经证明了脑干在自闭症的病理生物学中的潜在作用。先前的研究表明，脑干体积减少，并且该结构与感觉异常之间存在关系。然而，对于儿童期和青春期的脑干发育方面，我们知之甚少。本研究旨在通过使用纵向研究设计，通过 MRI 体积测量来检查脑干发育。参与者包括 23 名自闭症男孩和 23 名匹配的对照组（年龄范围为 8-17 岁），所有人均无智力障碍。参与者在基线时进行了一次结构 MRI 扫描，并在两年时进行了一次随访。使用 BRAINS2 软件包进行了脑干体积测量。在年龄、性别、惯用手和总脑容量方面，自闭症组和对照组没有显著差异；但是对照组的全智商较高。自闭症组和对照组的脑干体积增长模式不同。虽然对照组的整个脑干体积在两年期间保持稳定，但自闭症组随着年龄的增长而增加，到 15 岁时其体积与对照组相当。整个脑干体积的增加主要是由双侧灰质体积的增加驱动的。这项初步研究的结果表明，自闭症中存在发育性脑干异常，主要涉及灰质结构。这些发现与将自闭症视为具有大脑生长轨迹改变的神经发育障碍的概念是一致的。需要更多的纵向 MRI 研究来整合纵向认知/行为数据，以确认和阐明这些异常生长模式的临床意义。
