Stability of resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone in adolescent females exposed to child maltreatment

The experience of child maltreatment is a known risk factor for the development of psychopathology. Structural and functional modifications of neural systems implicated in stress and emotion regulation may provide one mechanism linking early adversity with later outcome. The authors examined two well-documented biological markers of stress vulnerability [resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone] in a group of adolescent females exposed to child maltreatment (n = 38; M age = 14.47) and their age-matched non-maltreated (n = 25; M age = 14.00) peers. Maltreated females exhibited greater relative right frontal EEG activity and lower cardiac vagal tone than controls over a 6-month period. In addition, frontal EEG asymmetry and cardiac vagal tone remained stable in the maltreated group across the 6 months, suggesting that the neurobiological correlates of maltreatment may not simply reflect dynamic, short-term changes but more long lasting alterations. The present findings appear to be the first to demonstrate stability of two biologically based stress-vulnerability measures in a maltreated population. Findings are discussed in terms of plasticity within the neural circuits of emotion regulation during the early childhood period and alternative causal models of developmental psychopathology.