Childhood and early adolescent aggression: Relationships with neural structure, neural function during processing of emotional facial expressions, and inhibitory task performance

Aggressive behavior's broad and negative impact includes poor outcomes for both aggressors (e.g., Angold, Costello & Erkanli, 1999; Heilbron & Prinstein, 2008) and victims (e.g., Menesini, Modena, & Tani, 2009; Tharp-Taylor, Haviland, & D'Amico, 2009). In spite of serious negative consequences, the etiology of aggressive behavior, and especially neural correlates of aggressive behavior are only beginning to be understood. The current investigation examined the relationship of aggressive behavior at Preschool and School Age with neural structure, function, and inhibitory performance at age 15. Participants were 80 (44 female) adolescents followed longitudinally since birth as part of the Wisconsin Study of Families and Work. At age 15, participants completed a structural and functional neuroimaging session, which included an inhibitory Go/No-Go task with emotional face and nonsocial control stimuli. Variables of interest were amygdala volume, neural response in brain regions important for processing emotional and social stimuli, and behavioral performance on the Go/No-Go task. Results revealed that males showing increased Preschool aggressive behavior had smaller amygdala volume as well as decreased neural response to emotional facial expressions in the amygdala, anterior cingulate, and fusiform gyrus. Relationships remained significant after accounting for concurrent symptoms of depression, anxiety, and inattention/impulsivity, as well as after accounting for symptoms of callousness and low empathy. For the relationship of Preschool aggression with amygdala activation, results were also significant beyond the effects of amygdala volume. Comparable relationships with neural structure and function were not observed for School Age aggression, and no significant relationships of aggressive behavior with neural structure or function were observed for females. Higher levels of School Age aggression related to poorer performance on face trials of the Go/No-Go task in both males and females.