Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Neuropsychobiology. 2013;68(3):181-8. doi: 10.1159/000354866. Epub 2013 Oct 24.
Individuals with autistic spectrum disorder (ASD) demonstrate an impaired ability to infer the mental states of others from their gaze. Thus, investigating the relationship between ASD and eye gaze processing is crucial for understanding the neural basis of social impairments seen in individuals with ASD. In addition, characteristics of ASD are observed in more comprehensive visual perception tasks. These visual characteristics of ASD have been well-explained in terms of the atypical relationship between high- and low-level gaze processing in ASD.
We studied neural activity during gaze processing in individuals with ASD using magnetoencephalography, with a focus on the relationship between high- and low-level gaze processing both temporally and spatially. Minimum Current Estimate analysis was applied to perform source analysis of magnetic responses to gaze stimuli.
The source analysis showed that later activity in the primary visual area (V1) was affected by gaze direction only in the ASD group. Conversely, the right posterior superior temporal sulcus, which is a brain region that processes gaze as a social signal, in the typically developed group showed a tendency toward greater activation during direct compared with averted gaze processing.
These results suggest that later activity in V1 relating to gaze processing is altered or possibly enhanced in high-functioning individuals with ASD, which may underpin the social cognitive impairments in these individuals.
自闭症谱系障碍(ASD)个体在从他人的注视推断他人的心理状态方面存在障碍。因此,研究 ASD 与目光处理之间的关系对于理解 ASD 个体中存在的社交障碍的神经基础至关重要。此外,在更全面的视觉感知任务中也观察到了 ASD 的特征。这些 ASD 的视觉特征可以用 ASD 中高低水平的目光处理之间的异常关系来很好地解释。
我们使用脑磁图研究了 ASD 个体在目光处理过程中的神经活动,重点关注了高低水平的目光处理在时间和空间上的关系。最小电流估计分析被应用于对目光刺激的磁响应进行源分析。
源分析表明,初级视觉区(V1)的后期活动仅在 ASD 组中受到注视方向的影响。相反,在典型发育组中,作为社会信号处理注视的右后颞上沟在直接注视处理时表现出比回避注视处理时更大的激活倾向。
这些结果表明,ASD 高功能个体中与目光处理相关的 V1 的后期活动发生改变或可能增强,这可能是这些个体存在社交认知障碍的基础。