Temperamental Shyness and Anger/Frustration in Childhood: Normative Development, Individual Differences, and the Impacts of Maternal Intrusiveness and Frontal Electroencephalogram Asymmetry.

This study used latent growth curve modeling to identify normative development and individual differences in the developmental patterns of shyness and anger/frustration across childhood. This study also examined the impacts of maternal intrusiveness and frontal electroencephalogram (EEG) asymmetry at age 4 on the developmental patterns of shyness and anger/frustration. 180 children (92 boys, 88 girls; Mage  = 4.07 years at baseline; 75.6% White, 18.3% Black, 6.1% multiracial/other) participated in the study. Normative development included significant linear decreases in shyness and anger/frustration. Individual variation existed in the developmental patterns. Children with left frontal EEG asymmetry showed a faster decreasing pattern of shyness. Children who experienced higher maternal intrusiveness and had left frontal EEG asymmetry showed a slower decreasing pattern of anger/frustration.