Fowler Carina H, Bogdan Ryan, Gaffrey Michael S
Department of Psychology & Neuroscience, Duke University, Reuben-Cooke Building, 417 Chapel Drive, Durham, NC, 27708, USA.
Department of Psychological and Brain Sciences, Washington University in St. Louis, Somers Family Hall, Forsyth Blvd, St. Louis, Missouri, 63105, USA.
Neurobiol Stress. 2021 Apr 22;14:100329. doi: 10.1016/j.ynstr.2021.100329. eCollection 2021 May.
Rodent research suggests that dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and the resulting cortisol stress response can alter the structure of the hippocampus and amygdala. Because early-life changes in brain structure can produce later functional impairment and potentially increase risk for psychiatric disorder, it is critical to understand the relationship between the cortisol stress response and brain structure in early childhood. However, no study to date has characterized the concurrent association between cortisol stress response and hippocampal and amygdala volume in young children. In the present study, 42 young children ( = 5.97, = 0.76), completed a frustration task and cortisol response to stress was measured. Children also underwent magnetic resonance imaging (MRI), providing structural scans from which their hippocampal and amygdala volumes were extracted. Greater cortisol stress response was associated with reduced right amygdala volume, controlling for whole brain volume, age, sex, and number of cortisol samples. There were no significant associations between cortisol stress response and bilateral hippocampus or left amygdala volumes. The association between right amygdala volume and cortisol stress response raises the non-mutually exclusive possibilities that the function of the HPA axis may shape amygdala structure and/or that amygdala structure may shape HPA axis function. As both cortisol stress response and amygdala volume have been associated with risk for psychopathology, it is possible that the relationship between cortisol stress response and amygdala volume is part of a broader pathway contributing to psychiatric risk.
啮齿动物研究表明，下丘脑 - 垂体 - 肾上腺（HPA）轴功能失调以及由此产生的皮质醇应激反应会改变海马体和杏仁核的结构。由于生命早期大脑结构的变化会导致后期功能受损，并可能增加患精神疾病的风险，因此了解幼儿期皮质醇应激反应与大脑结构之间的关系至关重要。然而，迄今为止，尚无研究描述幼儿皮质醇应激反应与海马体和杏仁核体积之间的并发关联。在本研究中，42名幼儿（平均年龄 = 5.97岁，标准差 = 0.76）完成了一项挫折任务，并测量了他们对压力的皮质醇反应。儿童还接受了磁共振成像（MRI）检查，提供了结构扫描图像，从中提取了他们的海马体和杏仁核体积。在控制了全脑体积、年龄、性别和皮质醇样本数量后，更大的皮质醇应激反应与右侧杏仁核体积减小有关。皮质醇应激反应与双侧海马体或左侧杏仁核体积之间没有显著关联。右侧杏仁核体积与皮质醇应激反应之间的关联提出了两种并非相互排斥的可能性，即HPA轴的功能可能塑造杏仁核结构和/或杏仁核结构可能塑造HPA轴功能。由于皮质醇应激反应和杏仁核体积都与精神病理学风险相关，因此皮质醇应激反应与杏仁核体积之间的关系可能是导致精神疾病风险的更广泛途径的一部分。
