Early Aggression, Social Competence, and Peer Rejection: Associations with Physiological Indices of Emotional Functioning

Open Access
Kalvin, Carla Beth
Graduate Program:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 05, 2014
Committee Members:
  • Karen Linn Bierman, Thesis Advisor
  • Aggression
  • social competence
  • peer rejection
  • emotional reactivity
  • emotion regulation
  • heart rate
  • P300
While recent research has supported the role of emotional functioning in the development of childhood aggression, little work has investigated the role of physiological indicators of emotional functioning in the manifestation of aggression and peer relations in young children. The present study examined associations among physiological measures of emotional functioning, aggression, social competence, and peer rejection in children with early-starting aggressive behaviors. Participants included 207 children with elevated aggression at kindergarten entry (73% African American, 19% Latino, 8% Caucasian; 66% male; average age 5.62 years at kindergarten entry). Aggressive behavior and social competence was assessed via teacher ratings and peer sociometric nominations, and peer preference was assessed via peer sociometric nominations. Two physiological indicators of emotional functioning were collected: heart rate reactivity in response to emotionally evocative movie scenes (used as an index of emotional reactivity), and the P300 component of the event-related potential in response to unfavorable reward conditions during an attention task (used as an index of emotion regulation). Heightened heart rate reactivity and reduced P300 were associated with elevated aggression and reduced social competence. While linear regression models revealed no direct effects between the physiological indicators of emotional functioning and peer preference, elevated aggression and reduced social competence were associated with peer rejection. The results of the study support the contribution of physiological indices of emotional reactivity and emotion regulation to aggression and socially adaptive behavior, as well as the role of aggression and social competence in peer rejection. Results suggest that exploration of the associations among emotional functioning, social behavior and peer rejection over time warrants future research.