Frontal brain electrical activity in infants of depressed and nondepressedmothers: Relation to variations in infant behavior

In previous studies, infants of depressed mothers have been found to exhibi t reduced left frontal brain electrical activity (EEG). The left frontal re gion has been hypothesized to mediate social approach behaviors and positiv e affective expression. These findings raise important questions about the cause and nature of atypical EEG patterns in infants of depressed mothers. The present study begins to address some of these questions by examining wh ether or nor variations in patterns of frontal brain activity in infants of depressed and nondepressed mothers are related to variations in infant beh avior as observed in naturalistic situations. If such relations exist, are they specific to certain behaviors hypothesized to be mediated by the front al region (i.e., positive approach behaviors)? Frontal and parietal brain e lectrical activity was recorded from 14- to 15-month old infants of depress ed versus nondepressed mothers during a baseline condition and during condi tions designed to elicit interest and positive affect. Infant behavior was observed in naturalistic play conditions, with and without mother, on a sep arate day from EEG resting. Mothers provided information on infant temperam ent. Infants of depressed mothers showed less affection and touching of the ir mothers. For infants of depressed mothers only, reduced left frontal bra in activity was found to be related to lower levels of affection toward mot her, but not to infant temperament. Furthermore, increased generalized fron tal activation was found to be related to higher levels of negative affect, hostility, and tantrums and aggression. Relations between infant brain act ivity and behavior were not found for parietal EEG activity. These results suggest that infant frontal electrical brain activity is related to variati ons in infant behavior, especially those involved in positive affiliative b ehavior and the expression and regulation of negative affect. The nature an d cause of atypical patterns of brain activity and question of whether such atypical patterns of frontal brain activity predispose infants to affectiv e disorders in later life are discussed.