Effects of childhood poverty and chronic stress on emotion regulatory brain function in adulthood

Abstract

Childhood poverty has pervasive negative physical and psychological health sequelae in adulthood. Exposure to chronic stressors may be one underlying mechanism for childhood poverty-health relations by influencing emotion regulatory systems. Animal work and human cross-sectional studies both suggest that chronic stressor exposure is associated with amygdala and prefrontal cortex regions important for emotion regulation. In this longitudinal functional magnetic resonance imaging study of 49 participants, we examined associations between childhood poverty at age 9 and adult neural circuitry activation during emotion regulation at age 24. To test developmental timing, concurrent, adult income was included as a covariate. Adults with lower family income at age 9 exhibited reduced ventrolateral and dorsolateral prefrontal cortex activity and failure to suppress amygdala activation during effortful regulation of negative emotion at age 24. In contrast to childhood income, concurrent adult income was not associated with neural activity during emotion regulation. Furthermore, chronic stressor exposure across childhood (at age 9, 13, and 17) mediated the relations between family income at age 9 and ventrolateral and dorsolateral prefrontal cortex activity at age 24. The findings demonstrate the significance of childhood chronic stress exposures in predicting neural outcomes during emotion regulation in adults who grew up in poverty.

Keywords: childhood adversity; fMRI; reappraisal; socioeconomic status.

Fig. 1.

The upper panels are regions showing a significant association with family income-to-needs ratio at age 9. (A) Dorsolateral prefrontal cortex (PFC) (x, y, z = –40, 12, 28; 343 voxels; P < 0.05, corrected). (B) Ventrolateral PFC, insula, temporopolar area (x, y, z = –46, 10, –8; 672 voxels; P < 0.05, corrected). (C) Amygdala (x, y, z = –30, –4, –22; 140 voxels; P < 0.05, uncorrected). The lower panels depict partial regression plots describing the associations between family income-to-needs ratio at age 9 and parameter estimates of a region in the contrast of Reappraisal vs. Maintain, controlling for adult income level.

Fig. 2.

A path diagram showing a mediation model with the unstandardized coefficients for each association. Chronic stress exposure across ages 9–17 mediated the relationship between family income-to-needs ratio and neural activity during Reappraisal in (A) dorsolateral prefrontal cortex (DLPFC) and (B) ventrolateral prefrontal cortex (VLPFC). ***P < 0.001, *P < 0.05.