The Relationship Between Early and Recent Life Stress and Emotional Expression Processing—A Functional Connectivity Study
The aim of this study was to characterize neural activation during the processing of negative facial expressions in a non-clinical group of individuals who experienced only early life stress, only recent life stress, both, or neither. Two models of stress consequences were investigated: the match/mismatch and cumulative stress models. The match/mismatch model assumes that early adversities may promote optimal coping with similar events in the future through fostering the development of coping strategies. The cumulative stress model assumes that effects of stress are additive, regardless of the timing of the stressors. Previous studies have suggested that stress can have both cumulative and match/mismatch effects on brain structure and functioning and, consequently, we hypothesized that effects on brain circuitry would be found for both models. We anticipated effects on the neural circuitry of structures engaged in face perception and emotional processing and, hence, the amygdala, fusiform face area, occipital face area, and posterior superior temporal sulcus were selected as seeds for seed-based functional connectivity analyses. We found that both the interaction between early and recent life stress, as well as cumulative stress levels, were related to alterations in functional connectivity during emotional facial expressions processing. This study adds to the growing body of literature suggesting that both the cumulative and the match/mismatch hypotheses are useful in explaining the effects of stress on humans.