Normandie univ, UNICAEN, PSL Université Paris, EPHE, INSERM, U1077, CHU de Caen, GIP Cyceron, Neuropsychologie et Imagerie de la Mémoire Humaine, 14000, Caen, France.
Université de Paris, LaPsyDÉ, CNRS, F-75005, Paris, France.
J Neurodev Disord. 2022 Aug 27;14(1):47. doi: 10.1186/s11689-022-09456-8.
Autism spectrum disorder (ASD) is associated with atypical neural activity in resting state. Most of the studies have focused on abnormalities in alpha frequency as a marker of ASD dysfunctions. However, few have explored alpha synchronization within a specific interest in resting-state networks, namely the default mode network (DMN), the sensorimotor network (SMN), and the dorsal attention network (DAN). These functional connectivity analyses provide relevant insight into the neurophysiological correlates of multimodal integration in ASD.
Using high temporal resolution EEG, the present study investigates the functional connectivity in the alpha band within and between the DMN, SMN, and the DAN. We examined eyes-closed EEG alpha lagged phase synchronization, using standardized low-resolution brain electromagnetic tomography (sLORETA) in 29 participants with ASD and 38 developing (TD) controls (age, sex, and IQ matched).
We observed reduced functional connectivity in the ASD group relative to TD controls, within and between the DMN, the SMN, and the DAN. We identified three hubs of dysconnectivity in ASD: the posterior cingulate cortex, the precuneus, and the medial frontal gyrus. These three regions also presented decreased current source density in the alpha band.
These results shed light on possible multimodal integration impairments affecting the communication between bottom-up and top-down information. The observed hypoconnectivity between the DMN, SMN, and DAN could also be related to difficulties in switching between externally oriented attention and internally oriented thoughts.
自闭症谱系障碍（ASD）与静息状态下的异常神经活动有关。大多数研究都集中在 alpha 频率异常作为 ASD 功能障碍的标志物上。然而，很少有研究探索静息态网络（DMN）、感觉运动网络（SMN）和背侧注意网络（DAN）内特定的 alpha 同步性。这些功能连接分析为 ASD 中多模态整合的神经生理相关性提供了相关见解。
本研究使用高时间分辨率 EEG 研究了 DMN、SMN 和 DAN 内和之间 alpha 频段的功能连接。我们使用标准化低分辨率脑电磁层析成像（sLORETA）检查了 29 名 ASD 患者和 38 名发育中（TD）对照组（年龄、性别和智商匹配）闭眼 EEG alpha 滞后相位同步。
与 TD 对照组相比，ASD 组在 DMN、SMN 和 DAN 内和之间的功能连接减少。我们在 ASD 中确定了三个连接障碍的枢纽：后扣带回皮质、楔前叶和内侧额回。这三个区域在 alpha 频段的电流源密度也降低了。
这些结果揭示了可能影响上下信息交流的多模态整合障碍。DMN、SMN 和 DAN 之间观察到的连接减少也可能与在外部定向注意和内部定向思维之间切换的困难有关。
