Infants of depressed mothers are more likely than infants of nondepressed mothers to have atypical brain activity, according to researchers at the University of Washington's Department of Psychology and Center on Human Development and Disability. When compared to infants of nondepressed mothers, infants of depressed mothers had less left frontal electroencephalogram (EEG) activity relative to right frontal EEG activity.
"Our results suggest that maternal depression may alter frontal brain activity which is associated with positive emotions," said Geraldine Dawson, PhD, head of the study. "This effect may be caused by the mother?s depression increasing the child's threshold for experiencing emotions such as joy and interest."
EEGs were used to record brain activity in 99 infants who were 13 to 15 months old. The infants' mothers included 59 depressed and 40 nondepressed adult women. The mothers were carefully assessed for depression and screened for difficulties such as substance abuse that could affect their infants. The results of the study appear in the current issue of Child Development.
EEG recordings were made during a non-social baseline situation and four emotion-eliciting social situations, including the mother silently playing with the infant, a stranger silently approaching the infant and then leaving the room, a familiar research assistant silently playing with the infant, and the mother leaving the room and then returning to the infant.
In the non-social situations and two of the playful-interaction situations, one with the mother and one with the familiar researcher, infants of the depressed mothers showed less left frontal EEG activity than right frontal EEG activity, compared to infants of the nondepressed mothers.