McConnell Brain Imaging Centre (BIC), Montreal Neurological Institute (MNI), Faculty of Medicine, McGill University, Montreal, Quebec, Canada.
Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada.
J Neurophysiol. 2021 Dec 1;126(6):2138-2157. doi: 10.1152/jn.00339.2021. Epub 2021 Nov 24.
Social interaction complexity makes humans unique. But in times of social deprivation, this strength risks exposure of important vulnerabilities. Human social neuroscience studies have placed a premium on the default network (DN). In contrast, hippocampus (HC) subfields have been intensely studied in rodents and monkeys. To bridge these two literatures, we here quantified how DN subregions systematically covary with specific HC subfields in the context of subjective social isolation (i.e., loneliness). By codecomposition using structural brain scans of ∼40,000 UK Biobank participants, loneliness was specially linked to midline subregions in the uncovered DN patterns. These association cortex patterns coincided with concomitant HC patterns implicating especially CA1 and molecular layer. These patterns also showed a strong affiliation with the fornix white matter tract and the nucleus accumbens. In addition, separable signatures of structural HC-DN covariation had distinct associations with the genetic predisposition for loneliness at the population level. The hippocampus and default network have been implicated in rich social interaction. Yet, these allocortical and neocortical neural systems have been interrogated in mostly separate literatures. Here, we conjointly investigate the hippocampus and default network at a subregion level, by capitalizing structural brain scans from ∼40,000 participants. We thus reveal unique insights on the nature of the "lonely brain" by estimating the regimes of covariation between the hippocampus and default network at population scale.
社会互动的复杂性使人类独一无二。但在社会隔离时期，这种优势可能会暴露出重要的脆弱性。人类社会神经科学研究一直关注默认网络 (DN)。相比之下，海马体 (HC) 的各个亚区在啮齿动物和猴子中得到了深入研究。为了弥合这两种文献之间的差距，我们在这里量化了在主观社会隔离（即孤独感）的背景下，DN 亚区如何与特定的 HC 亚区系统地相关。通过对约 40000 名英国生物银行参与者的大脑扫描进行代码分解，孤独感与未覆盖的 DN 模式中的中线亚区特别相关。这些联合皮层模式与伴随的 HC 模式一致，特别是 CA1 和分子层。这些模式还与穹窿白质束和伏隔核有很强的联系。此外，结构 HC-DN 协变的可分离特征与人群水平上孤独感的遗传易感性有明显的关联。海马体和默认网络都与丰富的社会互动有关。然而，这些皮质下和新皮质的神经系统在大多独立的文献中被分别研究。在这里，我们通过利用来自约 40000 名参与者的大脑扫描，共同研究海马体和默认网络的亚区水平。因此，通过估计海马体和默认网络在人群规模上的协变规律，我们揭示了“孤独大脑”的独特本质。
