Dr. Kimberly L Day

While self-regulation is believed to include both cognitive and emotional aspects, researchers often focus on children’s emotional regulation as a predictor of their angry, aggressive behavior without also considering the role that children’s cognitive regulation may play. The purpose of this study was to investigate how both cognitive and emotional regulation longitudinally predicted children’s aggressive behavior. Children (N = 92) and their mothers participated in a study when children were in preschool (T1) and middle childhood (T2). At T1, mothers completed the Childhood Behavior Questionnaire – Short Form (Putnam & Rothbart, 2006) as a measure of effortful control. Preschoolers were observed completing a locked box frustration task during which children’s social speech to mothers and private speech was transcribed. Private speech was categorized as one of five mutually exclusive categories: vocalizations, inaudible muttering, task-irrelevant, negatively valenced task-relevant, and facilitative task-relevant. Approximately four years later, mothers completed the Childhood Behavior Checklist for Ages 6-8 (Achenbach, 1991) and teachers completed the Teacher Report Form for Ages 6-8 (Achenbach, 1991) as a measure of children’s aggressive behavior. Preschoolers with greater effortful control had lower levels of aggressive behavior four years later. In addition, children who spoke more social speech had higher levels of aggressive behavior, which was predicted above and beyond their effortful control. While children’s private speech did not directly predict their aggressive behavior, a significant interaction was found in that children who had more effortful control and used more inaudible muttering had lower levels of aggression. These findings support the importance of developing optimal patterns of both cognitive and emotional regulation early in life.