Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland.
Hum Brain Mapp. 2018 Jun;39(6):2391-2404. doi: 10.1002/hbm.24009. Epub 2018 Mar 5.
To refine our understanding of autism spectrum disorders (ASD), studies of the brain in dynamic, multimodal and ecological experimental settings are required. One way to achieve this is to compare the neural responses of ASD and typically developing (TD) individuals when viewing a naturalistic movie, but the temporal complexity of the stimulus hampers this task, and the presence of intrinsic functional connectivity (FC) may overshadow movie-driven fluctuations. Here, we detected inter-subject functional correlation (ISFC) transients to disentangle movie-induced functional changes from underlying resting-state activity while probing FC dynamically. When considering the number of significant ISFC excursions triggered by the movie across the brain, connections between remote functional modules were more heterogeneously engaged in the ASD population. Dynamically tracking the temporal profiles of those ISFC changes and tying them to specific movie subparts, this idiosyncrasy in ASD responses was then shown to involve functional integration and segregation mechanisms such as response inhibition, background suppression, or multisensory integration, while low-level visual processing was spared. Through the application of a new framework for the study of dynamic experimental paradigms, our results reveal a temporally localized idiosyncrasy in ASD responses, specific to short-lived episodes of long-range functional interplays.
为了更深入地了解自闭症谱系障碍（ASD），需要在动态、多模态和生态实验环境中研究大脑。一种方法是比较 ASD 和典型发育（TD）个体在观看自然电影时的神经反应，但刺激的时间复杂性阻碍了这项任务，并且内在功能连接（FC）的存在可能会掩盖电影驱动的波动。在这里，我们检测了受试者间功能相关性（ISFC）瞬态，以在探测 FC 动态时将电影引起的功能变化与基础静息状态活动区分开来。当考虑电影在整个大脑中引发的显著 ISFC 波动的数量时，远程功能模块之间的连接在 ASD 人群中更多地参与其中。动态跟踪这些 ISFC 变化的时间分布，并将其与特定的电影片段联系起来，ASD 反应的这种特殊性涉及到功能整合和分离机制，如反应抑制、背景抑制或多感官整合，而低水平视觉处理则不受影响。通过应用一种新的动态实验范式研究框架，我们的结果揭示了 ASD 反应中的一种时间局部性的特殊性，这种特殊性是短暂的长程功能相互作用的结果。
