| This project examines commonalities and differences between aggressive and nonaggressive forms of antisocial behavior (ASB) using methodologies of behavioral genetics and EEG spectral power analysis. Using a longitudinal community sample of 1550 Los Angeles area twins, data were collected at two waves: Wave 1 (age 9-10 years) and Wave 3 (age 14-15 years). ASB was assessed using parent reports of the Child Behavioral Checklist (Achenbach, 1991), using the aggression and delinquency (non-aggressive antisocial behavior) scales. Biometric statistical modeling was applying to the twin variances and covariances in order to discern the pattern of genetic and environmental influences on aggressive and nonaggressive ASB across the two waves of data collection. Findings supported both the commonality and the distinction between these forms of ASB, as 44-79% of the influences were found to be shared through a latent common factor of ASB, and the rest were unique to each scale. Additive genetic, shared environmental and nonshared environmental effects were found to influence both time points; new influences in adolescence were exclusively genetic. EEG data from an open-eyed 3-minute resting period were used with principal components analysis to derive power scores in the frontal (channels: F8, F4, Fz, F3, F7, Af3, Af4, Fp1, Fp2) and parietal (channels: P8, P4, Pz, P3, P7) regions in the frequency ranges of theta (4-8 Hz), Alpha (8-10.5 Hz), and beta (10.5-30 Hz). Support was found for higher frontal alpha power, as well as higher frontal and parietal beta power, in association with Wave 3 aggressive ASB in the males. No significant relationships were found in the females, and none with nonaggressive ASB. Also, no significant concurrent relationships emerged. Bivariate genetic modeling found a small but significant genetic overlap (Rg=0.22) between frontal alpha power and aggressive ASB in the males, which entirely accounted for the phenotypic correlation between them. This study provides some replication for past findings of low arousal and ASB, but suggests that: 1. These relationship may exist for aggressive but not nonaggressive ASB. 2. Females may not show identical arousal patterns in relation to ASB. 3. Relationships may be less pronounced in community rather than clinical or criminal samples. |
