A consequence of toxic stress
This study is part of a growing body of work on the influence of “toxic stress” and other forms of PTSD on brain architecture. The authors note that prolonged exposure to adverse experiences leads to excessive activation of stress-response systems and accumulation of stress hormones. This disrupts immune and metabolic regulatory systems that influence the developing structures of the brain.
The study helps to contradict the “pseudoscientific falsehood” of biologic race-related differences in brain volume, instead emphasizing the role of adversity brought on by structural racism, the authors add.
In an accompanying editor’s note, the publication’s Editor-in-Chief Ned H. Kalin, MD, called childhood adversity, maltreatment, and stress, “significant risk factors for the development of psychopathology.”
These findings are “critically important, as they speak to the need for psychiatry as a field to be outspoken about the detrimental psychological impacts of race-related disparities in childhood adversity, to call out the fact that these disparities stem from structural racism, and to vigorously support rectifying efforts by pursuing policy changes,” he stated in a news release.
Social construct?
Joan Luby, MD, coauthor of an accompanying editorial, said she and her coauthor “really appreciate the study and think the findings are overall very consistent with the emerging literature, increasing the confidence [in the findings].”
Dr. Luby, a professor of child psychiatry and director of the Early Emotional Development Program, Washington University, St. Louis, noted that she “takes issue” with the fact that the study “makes inferences regarding race, when we think those inferences aren’t well justified, are misinterpretations, and could be misleading.”
Race is a “social construct” and there are many sources of adversity that the authors didn’t measure in the study and are likely the source of any remaining variance they found, including experiences of structural racism and discrimination,” said Dr. Luby, who was not involved in the study.
“How people look doesn’t have any bearing on their inherent biological characteristics, and more [needs to be studied] on how they experience the psychosocial environment and how the psychosocial environment rejects or reacts to them.”
These psychosocial issues “have to be taken into account and measured in a very comprehensive way,” she added.
The ABCD study was supported by the National Institutes of Health and additional federal partners. Dr. Harnett reports no relevant financial relationships. The other authors’ disclosures are listed on the original paper. Dr. Luby receives royalties from Guilford Press. Her coauthor reports no relevant financial relationships.
A version of this article first appeared on Medscape.com.