for research, Nathaniel Harnett, HMS An assistant professor of psychiatry and director of the Emotional Traumatic Experience Lab in Neurobiology at McLean Hospital, he led a team of researchers to study more than 7,300 white children and nearly 1,800 black children in the United States. children’s studies and MRI brain scans were analyzed. and 10 years old.
They found that black children displayed minor neurobiological differences compared with white children, reflecting lower amounts of gray matter in the amygdala, hippocampus, and prefrontal cortex. discovered.
Their analysis also revealed that experiencing adversity was an important differentiator, with household income being the most common predictor of differences in brain volume.
“Our study provides substantial evidence for the effects of structural racism on the developing brain in children. It may have meaning for happiness.
“Our study dataset included children under the age of 10. — Children with no choice of where they were born, who their parents were, or how much adversity they would face. These findings are a chilling reminder of the impact of systemic racism on public health and how important it is to address these disparities in a meaningful way. I will,” said Harnett.
In the United States, racial disparities are evident in the distribution of economic resources, exposure to stress, and prevalence of mental disorders. To date, few studies have investigated how racial inequalities in social determinants of health lead to brain changes in different groups.
Mining datasets to reveal disparities, neurological implications
For their research, Harnett and colleagues at McLean’s Institute of Neurobiology of Fear, founded and overseen by Kelly Ressler, Professor of Psychiatry at HMS and Chief Scientific Officer at McLean, and research studies Leveraged powerful datasets to look for potential race-related differences. The neurobiology of mental disorders and how racial and structural inequalities explain the differences.
Researchers reviewed data from a 2019 study on adolescent brain and cognitive development. This is a large-scale research effort involving approximately 12,000 U.S. children aged 9 to 10 in her 21 locations across the country.
Parents of study participants completed surveys assessing race and ethnicity of parents and children, parental education, employment and family income, and other variables. Participating children completed an assessment that captured emotional and physical conflicts within the home.
Also included was a measure of neighborhood deprivation using the Area Deprivation Index, which uses 17 socioeconomic indicators from the U.S. Census, including poverty and housing, to characterize a particular neighborhood.
The analysis found that parents of white children were three times more likely to be employed than parents of black children.
Parents of white children achieved higher levels of education and had higher family incomes than parents of black children. Specifically, about 75% of white parents have a college degree compared to about 41% of black parents, and about 47% of black parents have About 88% earn more than $35,000 a year.
White children also report fewer family conflicts, material difficulties, neighborhood disadvantages, and traumatic events than black children.
Evaluating the corresponding MRI data, experiencing childhood adversity was associated with decreased gray mass in the amygdala, hippocampus, and prefrontal cortex, and these effects may be seen in black children. It got higher.
The amygdala plays a key role in learning fear responses, the hippocampus is key to memory formation, and the prefrontal cortex regulates emotional and threat responses to fear.
Researchers observed neurobiological effects associated with most adversity indicators, with income being the most frequent predictor, affecting gray matter volume in eight of the 14 brain regions studied. gave the
Trauma history and family conflict were not associated with gray matter volume in any model. However, researchers note that this finding does not necessarily indicate an absence of neurobiological effects from these adversities.
“Overall brain differences are small and partially explained by differences in key socioeconomic status,” Harnett said. “It is the living adversity gap that has caused these differences.”
An additional analysis that considered previous studies on brain regions in PTSD and black children found that PTSD symptom severity was significantly higher, and symptom severity was further predicted by adversity.
Direction of future research
Building on these findings, the team plans to expand data collection beyond the ages included in this study to track the lifelong neurobiological impact of racial disparities in adversity. The researchers also wondered whether exposure to adversity could accelerate or slow brain aging, and whether additional measures of adversity not included in this study might be involved in these brain regions or psychiatric disorders. We would like to determine whether the area of
“These findings may be just the tip of the iceberg,” Harnett said.
Authorship, Funding and Disclosure
Additional authors include Nathalie Dumornay of McLean’s Depression and Anxiety Disorders Division and Lauren Lebois of McLean’s HMS Psychiatry and Depression and Anxiety Disorders Division.
Support for this research was provided by the National Institute of Mental Health (K00MH119603, K01MH118467, and U01MH110925).
Lebois is an unpaid member of the Scientific Committee of the International Society for Trauma Research, and her spouse is paid by Vanderbilt University for technology licensed to Acadia Pharmaceuticals. Ressler has served on the advisory boards or consultants of Acer, Bionomics, BioXcel, Brain Research Foundation, Janssen, Jazz Pharmaceuticals, Sage, Takeda, and Verily, and has received sponsored research support from Alkermes, Alto Neuroscience, BrainsWay, and Genomind. I have received ,Takeda. Other authors report no financial ties to commercial interests.
From McLean Hospital news release