Social interactions are a crucial aspect of human behaviour. Numerous neurophysiological studies have focused on socio-cognitive processes associated with the so-called theory of mind—the ability to attribute mental states to oneself and others. Theory of mind is closely related to social intelligence defined as a set of abilities that facilitate effective social interactions. Social intelligence encompasses multiple theory of mind components and can be measured by the Four Factor Test of Social Intelligence (the Guilford-Sullivan test). However, it is unclear whether the differences in social intelligence are reflected in structural brain differences. During the experiment, 48 healthy right-handed individuals completed the Guilford-Sullivan test. T1-weighted structural MRI images were obtained for all participants. Voxel-based morphometry analysis was performed to reveal grey matter volume differences between the two groups (24 subjects in each)—with high social intelligence scores and with low social intelligence scores, respectively. Participants with high social intelligence scores had larger grey matter volumes of the bilateral caudate. The obtained results suggest the caudate nucleus involvement in the neural system of socio-cognitive processes, reflected by its structural characteristics.

社交互动是人类行为的关键方面。许多神经生理学研究都集中在与所谓的心理理论相关的社会认知过程上，心理理论是将精神状态归因于自己和他人的能力。心智理论与社会智能密切相关，后者被定义为促进有效的社会互动的一组能力。社会智能包含多种心理理论成分，可以通过社会智能四因素测验（Guilford-Sullivan测验）进行衡量。但是，尚不清楚社会智能的差异是否反映在大脑的结构差异上。在实验过程中，有48位健康的惯用右手的人完成了吉尔福德-沙利文测试。为所有参与者获得了T1加权结构MRI图像。进行了基于体素的形态计量分析，以揭示两组（每组24个受试者）之间的灰质体积差异-分别具有较高的社会智力得分和较低的社会智力得分。社会智商高的参与者双侧尾状核的灰质量更大。获得的结果表明尾状核参与了社会认知过程的神经系统，反映了其结构特征。