Anger and Approach Motivation in Infancy: Relations to Early Childhood Inhibitory Control and Behavior Problems.

The relations among infant anger reactivity, approach behavior, and frontal EEG asymmetry, and their relations to inhibitory control and behavior problems in early childhood were examined within the context of a longitudinal study of temperament. Two hundred and nine infants' anger expressions to arm restraint were observed at 4 months of age. Infants' approach behaviors during play with an unpredictable toy and baseline frontal electroencephalogram (EEG) asymmetry were assessed at 9 months of age. Inhibitory control during a Go/No-Go task and parent-report of behavior problems were evaluated at 4 years of age. High anger-prone infants with left, but not right, frontal EEG asymmetry showed significantly more approach behaviors and less inhibitory control relative to less anger-prone infants. Although a link between anger proneness in infancy and behavior problems in early childhood was not found, a combination of low approach behaviors and poor inhibitory control was predictive of internalizing behaviors.