Department of Family Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA, 90089, USA.
Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, CA, 90089, USA.
Brain Imaging Behav. 2021 Aug;15(4):1718-1727. doi: 10.1007/s11682-020-00365-9.
Self-reported experiences of discrimination are associated with a number of negative health outcomes. However, the neurobiological correlates of discrimination remain elusive. Recent neuroimaging work suggests that the amygdala is sensitive to forms of social adversity and the insula is involved in assessments of trust. We hypothesized that functional connectivity (FC) of these brain regions may be associated with discrimination in older Black adults. One-hundred and twenty-four nondemented older Black adults participating in the Minority Aging Research Study or the Clinical Core study of the Rush Alzheimer's Disease Center completed a measure of self-reported experiences of discrimination and a 3T MRI brain scan including structural T1 and resting-state fMRI EPIBOLD sequences. The right and left amygdala and insula regions were anatomically delineated as ROIs according to the Harvard-Oxford Brain Atlas and whole-brain voxelwise FC analyses were conducted using default parameters in the CONN toolbox. In regression analyses controlling for demographics and global cognition, self-reported experiences of discrimination were associated with greater FC between the left insula and the bilateral intracalcarine cortex, weaker FC between the left insula and the left dorsolateral prefrontal cortex, and weaker FC between the right insula and the left supplementary motor area. Amygdala analyses yielded no significant findings. Greater self-reported experiences of discrimination are associated with differential insula functional connectivity in older adults. More specifically, results suggest that discrimination is associated with differential connectivity of a key region (the insula) involved in trust perception.
自我报告的歧视经历与许多负面健康结果有关。然而，歧视的神经生物学相关性仍然难以捉摸。最近的神经影像学研究表明，杏仁核对各种形式的社会逆境敏感，而脑岛则参与信任评估。我们假设这些大脑区域的功能连接（FC）可能与老年黑人中存在的歧视有关。124 名无痴呆的老年黑人参加了少数族裔衰老研究或拉什阿尔茨海默病中心的临床核心研究，完成了一项自我报告的歧视经历测量和 3T MRI 脑部扫描，包括结构 T1 和静息状态 fMRI EPIBOLD 序列。根据哈佛-牛津脑图谱对右侧和左侧杏仁核和脑岛区域进行了解剖学描绘，并使用 CONN 工具包中的默认参数进行了全脑体素水平的 FC 分析。在回归分析中，控制了人口统计学和整体认知，自我报告的歧视经历与左侧脑岛和双侧内距皮质之间更强的 FC 相关，与左侧脑岛和左侧背外侧前额叶皮质之间更弱的 FC 相关，与右侧脑岛和左侧补充运动区之间更弱的 FC 相关。杏仁核分析没有发现显著结果。更多的自我报告的歧视经历与老年人的岛叶功能连接的差异有关。更具体地说，结果表明歧视与信任感知相关的关键区域（脑岛）的连接差异有关。
