Childhood abuse delays maturation specific to emotion circuits in girls
Girls who have been exposed to abuse have a delayed structural maturation pattern specific to emotion circuitry, which is potentially an adaptive mechanism that enhances threat generalization, a study has found. On the other hand, physical neglect correlates with a broader brain-wide pattern of advanced structural maturation.
“Childhood abuse represents one of the most potent risk factors for developing psychopathology, especially in females,” the authors said. “Evidence suggests that exposure to early-life adversity may be related to advanced maturation of emotion processing neural circuits.”
A total of 234 girls (ages 8–18 years) from multiple sites completed clinical assessment, maltreatment histories, and high-resolution T1-weighted structural magnetic resonance imaging. They were further stratified by abuse history and internalizing disorder diagnosis into typically developing (no abuse/no diagnosis), resilient (abuse/no diagnosis), and susceptible (abuse/current diagnosis) groups.
The authors then aggregated machine learning models of normative brain development in a stacked generalization framework trained to predict chronological age using gray matter volume in whole-brain, emotion, and language circuit parcellations. They also calculated brain age gap estimations (BrainAGEs; predicted age minus true chronological age) as indices of relative circuit maturation.
Childhood abuse was associated with reduced BrainAGE (delayed maturation) specific to emotion circuits, and delayed emotion circuit BrainAGE was associated with increased hyperarousal symptoms. In contrast, childhood physical neglect correlated with increased whole-brain BrainAGE (advanced maturation).
Notably, neural contributors to emotion circuit BrainAGE differed between girls with and without an internalizing diagnosis, particularly in the lateral prefrontal, parietal, and insular cortices and the hippocampus.
“The differential influence of fronto-parietal cortices and the hippocampus on emotion circuit maturity in resilient girls may represent neurodevelopmental markers of reduced psychiatric risk following abuse,” the authors said.