The social brain hypothesis proposes that the complexity of human brains has coevolved with increasing complexity of social interactions in primate societies. The present study explored the possible relationships between brain morphology and the richness of more intimate ‘inner’ and wider ‘outer’ social circles by integrating Bayesian hierarchical modeling with a large cohort sample from the UK Biobank resource (n = 10 000). In this way, we examined population volume effects in 36 regions of the ‘social brain’, ranging from lower sensory to higher associative cortices. We observed strong volume effects in the visual sensory network for the group of individuals with satisfying friendships. Further, the limbic network displayed several brain regions with substantial volume variations in individuals with a lack of social support. Our population neuroscience approach thus showed that distinct networks of the social brain show different patterns of volume variations linked to the examined social indices.

中文翻译：

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社会人脑形态的人口变异性，包括社会支持，家庭规模和友谊满意度。

社会大脑假说提出，在灵长类社会中，人脑的复杂性与社交互动的复杂性不断发展。本研究中通过与来自英国生物库资源大队列样品（积分贝叶斯建模分层探索脑形态，更亲密“内”和更宽的“外部”社交圈的丰富性之间的可能关系Ñ = 10000）。通过这种方式，我们检查了“社交大脑”的36个区域（从较低的感觉到较高的联想皮层）的种群数量影响。对于具有令人满意的友谊的个人，我们在视觉感觉网络中观察到了强烈的音量效果。此外，边缘网络显示了几个缺乏社交支持的个体的大脑区域，这些区域的体积变化很大。因此，我们的人口神经科学方法表明，社交大脑的不同网络显示出与所检查的社交指标相关的不同数量变化模式。