Understanding the joint neurobiological and social bases to aggression is critical to future attempts to tackle this major public health problem. The overarching goals are: (a) to conduct perhaps the most systematic integration of biosocial risk factors for childhood aggression in order to predict later aggression, (b) to conduct one of the very few biosocial interventions on childhood aggression, (c) to predict and treat two fundamentally different manifestations of aggression proactive and reactive aggression which likely have different etiologies and responsiveness to treatment. The specific aims are: (1) to assess biological (genetic, neurocognitive, brain imaging, neuroendocrinological, neurotoxin, psychophysiological, nutritional), psychosocial (neighborhood, family, school, peer, psychological) and psychiatric (ADHD, CD, ODD, depression, anxiety, PTSD, schizophrenia-spectrum) risk factors for male and female aggression in order to better predict later aggression, (2) to improve prediction by identifying the genetic, neuroimaging, psychophysiological, and neuroendocrinological factors that protect children who are socially at risk for a violence outcome, (3) to develop a genetic mouse model of aggression to test the effectiveness of nutritional interventions in reducing aggression, (4) to begin to develop a new biosocial approach to the treatment and prevention of aggression, based on both cognitive-behavioral and nutrition interventions, (5) to assess the differential prediction and treatment of two fundamental variants of child aggression: proactive and reactive aggression. The human sample will consist of 500 male and female 11-year-old children drawn from high-risk communities in Philadelphia. Three hundred participants will engage in a baseline assessment for risk factors for aggression, and then be randomly assigned to one of four three-month intervention programs: treatment-as-usual, cognitive-behavioral intervention, nutrition supplementation, or CBI + nutrition. Aggression outcome will be assessed throughout intervention and post-intervention.

The investigators believe that biological risk factors will interact with social risk factors in predicting aggression, over and above main effects of these classes of risk factors. Treatment effectiveness will interact with risk factors: those with low omega-3 and high lead exposure at intake will benefit most from the nutritional intervention; those with cognitive and affective risk factors will benefit most from the neuro-cognitive-behavioral intervention.