背景:自闭症谱系障碍(ASD),一种神经发育障碍,由社会交往缺陷加上重复的行为和有限的兴趣定义,目前影响普通人群中的1/36儿童。脑功能成像的最新进展显示有望提供ASD诊断可能性的有用生物标志物,行为特征严重性,甚至对治疗干预的反应。然而,当前的金标准神经成像方法(例如,功能磁共振成像,由于受约束的成像环境,fMRI)在对ASD相关行为的基础脑功能的自然研究中受到限制。与功能磁共振成像相比,高密度扩散光学层析成像(HD-DOT),一种非侵入性和最小约束的光学神经成像模式,可以克服这些限制。在这里,我们旨在建立HD-DOT,以评估自闭症和非自闭症学龄儿童的脑功能,因为他们执行了先前显示的生物运动知觉任务,可产生与ASD诊断和行为特征相关的结果.
方法:我们使用HD-DOT对46名ASD学龄期参与者和49名非自闭症个体(NAI)的大脑功能进行成像,因为他们观察了相干生物学和乱序运动的动态点光显示。我们通过统计参数映射评估了组水平的皮质脑功能。此外,我们测试了大脑行为与自闭症特征维度指标的关联,用社会反应能力量表-2,用分层回归模型衡量。
结果:我们发现,NAI参与者在与视觉相关的皮质区域中表现出比ASD儿童更强的大脑活动对比(相干>乱序),电机,社会处理。此外,回归模型揭示了自闭症参与者的多个皮质区域,这些区域的脑功能与ASD特征的维度测量显著相关.
结论:光学成像方法的深度敏感性有限,因此无法测量皮质下深部区域的大脑活动。然而,该HD-DOT系统的视野包括先前涉及自闭症的基于任务和无任务研究的多个大脑区域。
结论:这项研究表明,HD-DOT对脑功能敏感,既区分NAI和ASD组,又与ASD特征的维度测量相关。这些发现将HD-DOT确立为研究自闭症和非自闭症儿童大脑功能的有效工具。此外,这项研究建立了与生物运动知觉相关的神经相关性及其与ASD特征的维度测量的关联。
Autism spectrum disorder (ASD), a neurodevelopmental disorder defined by social communication deficits plus repetitive behaviors and restricted interests, currently affects 1/36 children in the general population. Recent advances in functional brain imaging show promise to provide useful biomarkers of ASD diagnostic likelihood, behavioral trait severity, and even response to therapeutic intervention. However, current gold-standard neuroimaging methods (e.g., functional magnetic resonance imaging, fMRI) are limited in naturalistic studies of brain function underlying ASD-associated behaviors due to the constrained imaging environment. Compared to fMRI, high-density diffuse optical tomography (HD-DOT), a non-invasive and minimally constraining optical neuroimaging modality, can overcome these limitations. Herein, we aimed to establish HD-DOT to evaluate brain function in autistic and non-autistic school-age children as they performed a biological motion perception task previously shown to yield results related to both ASD diagnosis and behavioral traits.
We used HD-DOT to image brain function in 46 ASD school-age participants and 49 non-autistic individuals (NAI) as they viewed dynamic point-light displays of coherent biological and scrambled motion. We assessed group-level cortical brain function with statistical parametric mapping. Additionally, we tested for brain-behavior associations with dimensional metrics of autism traits, as measured with the Social Responsiveness Scale-2, with hierarchical regression models.
We found that NAI participants presented stronger brain activity contrast (coherent > scrambled) than ASD children in cortical regions related to visual, motor, and social processing. Additionally, regression models revealed multiple cortical regions in autistic participants where brain function is significantly associated with dimensional measures of ASD traits.
Optical imaging methods are limited in depth sensitivity and so cannot measure brain activity within deep subcortical regions. However, the field of view of this HD-DOT system includes multiple brain regions previously implicated in both task-based and task-free studies on autism.
This study demonstrates that HD-DOT is sensitive to brain function that both differentiates between NAI and ASD groups and correlates with dimensional measures of ASD traits. These findings establish HD-DOT as an effective tool for investigating brain function in autistic and non-autistic children. Moreover, this study established neural correlates related to biological motion perception and its association with dimensional measures of ASD traits.