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

Abstract

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.

Keywords: abuse; amygdala; cortisol; infancy; intergenerational transmission; neglect.

Figure 1.

Scatterplot Displaying Infant Age at Scan in Relation to Whole Brain Grey Matter Volume. Note. Age in Months: M=11.74; SD= 6.12; N = 56, 1 Outlier Removed; Brain Volume Metric is mm³; Correlation Between Age at Scan and Whole Brain Volume, r = .78, p < .001

Figure 2.

Trajectories of Infant Cortisol Levels Over the Still Face Procedure by Severity of Maternal Childhood Neglect and Abuse. Note. Low Abuse Defined as Equal to or Below the Mean; High Abuse Defined Above the Mean. Low Neglect Defined as Equal to or Below the Mean; High Neglect Defined as Above the Mean. Infant Cortisol Trajectories Among Mothers With High and Low Childhood Abuse are Shown by Solid Lines; Infant Cortisol Trajectories Among Mothers With High and Low Childhood Neglect are Shown by Dotted Lines. Error Bars Represent Standard Deviations Around the Group Means at Each Time Point

Figure 3.

(a, b) Standardized Coefficients and Confidence Intervals, as Well as Unstandardized Coefficients, From Mediation Models With Infant Cortisol Output Mediating the Associations Between Maternal Childhood Neglect Severity and Right Hemisphere (Figure 3a) and Left Hemisphere (Figure 3b) Amygdala Volumes. Note. WBV = Whole Brain Volume. CIs That do Not Contain Zero are Significant at p < .05.