Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada; Neurosciences and Mental Health Program, SickKids Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Psychology, University of Toronto, Toronto, Ontario, Canada.
Department of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada; Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2020 Sep;5(9):901-912. doi: 10.1016/j.bpsc.2020.04.007. Epub 2020 Apr 24.
Deficits in social communication are one of the main features of autism spectrum disorder (ASD). Adults with ASD show atypical brain activity during false-belief understanding, an aspect of social communication involving the ability to infer that an individual can have an incorrect belief about a situation. Our study is the first to investigate whether adults with ASD exhibit differences in frequency-specific functional connectivity patterns during false-belief reasoning.
We used magnetoencephalography to contrast functional connectivity underlying false-belief understanding between 40 adults with ASD and 39 control adults. We examined whole-brain phase synchrony measures during a false-belief task in 3 frequency bands: theta (4-7 Hz), alpha (8-14 Hz), and beta (15-30 Hz).
Adults with ASD demonstrated reduced theta-band connectivity compared with control adults between several right-lateralized and midline regions such as the medial prefrontal cortex, right temporoparietal junction, right inferior frontal gyrus, and right superior temporal gyrus. During false-belief trials, they also recruited a network in the beta band that included primary visual regions such as the bilateral inferior occipital gyri and the left anterior temporoparietal junction.
Reduced theta-band synchrony between areas associated with mentalizing, inhibition, and visual processing implies some difficulty in communication among these functions in ASD. This impairment in top-down control in the theta band may be counterbalanced by their engagement of a beta-band network because both the left anterior temporoparietal junction and beta-band oscillations are associated with attentional processes. Thus, adults with ASD demonstrate alternative neural mechanisms for successful false-belief reasoning.
社交沟通障碍是自闭症谱系障碍(ASD)的主要特征之一。患有 ASD 的成年人在理解错误信念时表现出异常的大脑活动,这是社交沟通的一个方面,涉及推断个体对情况可能存在错误信念的能力。我们的研究首次调查了 ASD 成年人在错误信念推理过程中是否表现出频率特异性功能连接模式的差异。
我们使用脑磁图对比了 40 名 ASD 成年人和 39 名对照组成年人在错误信念理解任务中的全脑相位同步测量值。我们在 3 个频带(θ波[4-7 Hz]、α波[8-14 Hz]和β波[15-30 Hz])下检查了错误信念任务中的功能连接。
与对照组成年人相比,ASD 成年人在几个右侧和中线区域(如内侧前额叶皮层、右侧颞顶联合区、右侧额下回和右侧颞上回)之间的θ带连接减少。在错误信念试验中,他们还招募了一个包括初级视觉区域(如双侧下枕叶和左侧颞顶联合区前部)的β带网络。
与心理化、抑制和视觉处理相关区域之间的θ带同步减少表明 ASD 中这些功能之间的沟通存在一些困难。这种θ带中自上而下控制的损伤可能被他们参与β带网络所平衡,因为左颞顶联合区前部和β带振荡都与注意过程有关。因此,患有 ASD 的成年人表现出成功进行错误信念推理的替代神经机制。