Background

Experiences of racial discrimination are linked to a range of negative brain health outcomes, but little is known about how these experiences impact neural architecture, including white matter microstructure, which may partially mediate these outcomes. Our goal was to examine associations between racially discriminatory experiences and white matter structural integrity in a sample of Black American women.

Methods

We recruited 116 Black American women as part of a long-standing study of trauma. Participants completed assessments of racial discrimination, trauma exposure, and posttraumatic stress disorder and underwent diffusion tensor imaging. Fractional anisotropy and mean diffusivity values were extracted from major white matter tracts throughout the brain.

Results

Experiences of racial discrimination were associated with significantly lower fractional anisotropy in multiple white matter tracts, including the corpus callosum, cingulum, and superior longitudinal fasciculus (ps < .004), even after accounting for variance associated with trauma, posttraumatic stress disorder, and demographic- and scanner-related factors.

Conclusions

These findings suggest that experiences of racial discrimination are independently related to decrements in white matter microarchitecture throughout the brain. In individuals who have experienced other types of adversity, racial discrimination clearly has additive and distinctive deleterious effects on white matter structure. Our findings suggest a pathway through which racial discrimination can contribute to brain health disparities in Black Americans; the deleterious contributions of racial discrimination on the microstructure of major white matter pathways may increase vulnerability for the development of neurodegenerative disorders as well as the development of mental health problems.

中文翻译：

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遭受创伤的黑人女性的种族歧视和白质微结构

背景

种族歧视的经历与一系列负面的大脑健康结果有关，但人们对这些经历如何影响神经结构（包括白质微结构）知之甚少，这可能部分调节这些结果。我们的目标是在美国黑人女性样本中检查种族歧视经历与白质结构完整性之间的关联。

方法

作为一项长期的创伤研究的一部分，我们招募了 116 名美国黑人女性。参与者完成了对种族歧视、创伤暴露和创伤后应激障碍的评估，并接受了弥散张量成像。从整个大脑的主要白质束中提取分数各向异性和平均扩散率值。

结果

即使在考虑了与创伤、创伤后应激障碍和人口统计和扫描仪相关因素。

结论

这些发现表明，种族歧视的经历与整个大脑白质微结构的减少独立相关。在经历过其他类型逆境的个人中，种族歧视显然对白质结构具有附加和独特的有害影响。我们的研究结果表明了种族歧视可能导致美国黑人大脑健康差异的途径；种族歧视对主要白质通路微观结构的有害贡献可能会增加神经退行性疾病发展的脆弱性以及心理健康问题的发展。