Maternal Childhood Neglect is Linked to Greater Infant Cortisol Levels and Larger Infant Limbic Volumes.

Studies have linked maternal childhood maltreatment to altered infant brain volumes, but none have examined infant hypothalamic-pituitary-adrenal (HPA) axis function as a mechanism linking the two domains. Further, studies among older children suggest that childhood abuse and neglect may be associated with different developmental outcomes and thus should be studied separately. Study participants were N = 57 mother-infant dyads, stratified for maternal childhood maltreatment. At 4 months, infant cortisol total output (AUCg) and change (AUCi) were assessed across the Still-Face Paradigm. Under natural sleep, infants completed T1-weighted MRI scans (M age = 12.28 months). Whole brain, amygdala, and hippocampal volumes were extracted via automated segmentation. Maternal childhood neglect, but not abuse, was directly associated with higher infant AUCg and AUCi, and was indirectly associated with larger amygdala and hippocampal volumes through infant AUCg. Results suggest that infant cortisol may be particularly influenced by maternal childhood neglect and may be one mechanism further influencing brain development.