Consistency of EEG asymmetry patterns in infants of depressed mothers.

We evaluated frontal electroencephalogram (EEG) asymmetry across multiple contexts as an index of a general affective response predisposition in 12-month-old infants whose mothers were at elevated risk for perinatal depression due to their mother's history of depression. We further examined mothers' prenatal, postnatal, and concurrent depressive symptom levels in relation to infants' frontal EEG asymmetry consistency. Mothers (n = 132) with a history of depression prior to pregnancy completed depressive symptom scales repeatedly during pregnancy and the first year postpartum. Their 12-month-old infants' frontal EEG asymmetry was recorded across five contexts (baseline/bubbles, peek-a-boo, play, feeding, and distract). Frontal EEG asymmetries showed small to moderate correlations across contexts. Mothers' prenatal depression symptom levels (not postnatal or concurrent) were associated with infants having consistent right, rather than left, frontal EEG asymmetry, even after controlling for infants' observed affect. These findings demonstrate the consistency of EEG asymmetry scores across contexts in 12-month-old infants at risk for the development of psychopathology, providing support for relative right frontal EEG asymmetry as a trait marker of vulnerability to depression. Findings also suggest the importance of mothers' prenatal, rather than postnatal or concurrent depression, in predicting infants' consistent patterns of relative right frontal EEG asymmetry across contexts.