Laura Baker: USC Dept. of Psychology

Human aggression and antisocial behavior are known to be the product of both social and biological risk factors. What is not yet understood is how environment and genetic factors may mediate the interrelationships among these risk factors and antisocial outcomes. A study of twins and their families provides the ideal opportunity to answer the critical question in this regard: Do measured social and biological variables relate to antisocial development for genetic or environmental reasons? Our ability to develop effective and efficient interventions for antisocial behavior rests critically upon the answer to this question.

Preliminary results will be presented from the 1st wave of an ongoing longitudinal study of antisocial and aggressive behavior in 600 twin pairs (both male and female), aged 9-10 years old during an initial assessment. The study provides the first opportunity to investigate the environmental and genetic underpinnings of important social and biological risk factors for unlawful, antisocial, and aggressive behavior in boys and girls on the brink of adolescence. Social risk factors include aspects of the family environment, such as socio-economic status, emotional climate, cohesion, parental warmth and affection, parental supervision, discipline and control. Specific environmental factors for each twin are also studied, including individual relationships with each family member, as well as peer-group characteristics. Biological risk factors include psychophysiological indicators of arousal (both electrodermal and cardiovascular channels), electrocortical measures of brain activity (using both EEG and ERP measures) as well as neuropsychological and cognitive testing. Both the social and biological risk factors studied will be shown to distinguish between children exhibiting varying levels of aggressive and antisocial behavior. Biometrical analyses of twin similarity for ASB and a selected group of these risk factors will be presented.