Bernhardt Boris C, Valk Sofie L, Silani Giorgia, Bird Geoffrey, Frith Uta, Singer Tania
Department of Social Neuroscience, Max-Planck-Institute of Human Cognitive and Brain Sciences, Leipzig, Germany.
Institute of Cognitive Neuroscience, University College London, London, UK Cognitive Neuroscience Sector, International School for Advanced Studies SISSA-ISAS, Trieste, Italy.
Cereb Cortex. 2014 Dec;24(12):3258-67. doi: 10.1093/cercor/bht182. Epub 2013 Jul 17.
Autism spectrum conditions (ASC) are neurodevelopmental disorders characterized by abnormal social cognition. A core feature of ASC is disrupted Theory of Mind (ToM), our ability to take the mental perspective of others. ASC is also associated with alexithymia, a trait characterized by altered emotional interoception and empathy. Here, we applied structural MRI covariance analysis to assess whether ASC and alexithymia differentially affect structural brain networks associated with sociocognitive and socioaffective functions. Based on previous functional MRI findings, we expected disrupted ToM networks (centered on dorsomedial prefontal cortex [dmPFC], and temporo-parietal junction [TPJ]) in ASC, while alexithymia would affect networks centered on fronto-insular cortex (FI), regions associated with interoception of emotion and empathy. Relative to controls, ASC indeed showed reduced covariance in networks centered on dmPFC and TPJ, but not within FI networks. Irrespective of ASC, covariance was negatively modulated by alexithymia in networks extending from FI to posterior regions. Network findings were complemented by self-reports, indicating decreased perspective taking but normal empathic concern in ASC. Our results show divergent effects of ASC and alexithymia on inter-regional structural networks, suggesting that networks mediating socioaffective processes may be separable from networks mediating sociocognitive processing.
自闭症谱系障碍（ASC）是一类以社会认知异常为特征的神经发育障碍。ASC的一个核心特征是心理理论（ToM）受损，即我们理解他人心理视角的能力。ASC还与述情障碍有关，述情障碍的特点是情绪内感受和共情能力改变。在此，我们应用结构磁共振成像协方差分析来评估ASC和述情障碍是否对与社会认知和社会情感功能相关的脑结构网络产生不同影响。基于先前的功能磁共振成像研究结果，我们预计ASC患者的ToM网络（以背内侧前额叶皮质[dmPFC]和颞顶联合区[TPJ]为中心）会受到破坏，而述情障碍会影响以额岛皮质（FI）为中心的网络，这些区域与情绪内感受和共情有关。相对于对照组，ASC患者确实在以dmPFC和TPJ为中心的网络中协方差降低，但在FI网络中没有。无论是否患有ASC，从FI延伸到后部区域的网络中，协方差都受到述情障碍的负向调节。网络研究结果得到了自我报告的补充，表明ASC患者的换位思考能力下降，但共情关注正常。我们的结果显示ASC和述情障碍对区域间结构网络有不同影响，表明介导社会情感过程的网络可能与介导社会认知过程的网络是可分离的。
