The effect of normal personality, psychopathy and attachment on anti-and prosocial outcomes

Psychopathy is a dangerous form of antisocial personality that is associated with aggressive and delinquent behaviour. This thesis investigated psychopathic traits in the normal population to assess the relationship to antisocial and prosocial behaviour. This was examined both psychometrically and behaviourally. Furthermore, it was examined if emotion-processing deficits existed between individuals with high and low psychopathic traits in the normal population. Study 1 examined if standard personality measures based on the Five-Factor Model (FFM) of Personality, as well as specific items aimed to index sub-clinical primary and secondary psychopathic traits, could predict psychopathy-related outcomes in 14 year olds. It was found that individuals with higher levels of Neuroticism (N) and lower levels of Conscientiousness (C) were at an increased risk of mental health problems. Higher levels of Extraversion (E) and lower levels of C were related to increased alcohol and drug use. Alcohol and drug use were also predicted by higher primary and secondary psychopathic-like traits. Study 2 examined alcohol use as well as both proactive and reactive aggression in relation to FFM traits and psychopathic traits in adolescents, and revealed that psychopathic traits were the best predictors of aggression. Alcohol use was best predicted by FFM traits at age 14. Study 3 was a replication of Study 2 using a young adult sample. Whereas alcohol use and proactive aggression were found to be best predicted by higher levels of psychopathic traits, as measured by the Youth Psychopathy Inventory, reactive aggression was most strongly predicted by high levels of N and low levels of Agreeableness (A). As it has been suggested that attachment may be an underlying mechanism involved in the deficits seen in psychopathic individuals, in the second part of the thesis it was assessed whether attachment plays a role in the relationship between psychopathy and emotion-processing as well as antisocial and prosocial behaviour. Study 4 confirmed psychometrically that psychopathy as measured by the YPI was related to attachment to parents as well as the dismissing-avoidant attachment style. Study 5 and 6 investigated the link between psychopathic traits and emotion-processing, prosocial and antisocial behaviour as well as the impact of attachment on these relationships. The results of these studies indicated that self-report psychopathy measures were related to antisocial outcomes psychometrically but failed to show predicted associations with prosocial and antisocial tendencies behaviourally. However, differences in emotion-processing were found between individuals with low and high levels of psychopathic traits. It was also found that FFM-based personality traits were useful in predicting psychopathy-related outcomes and can be effective in describing psychopathy-like traits. Finally, self-reported attachment did not impact the relationship between psychopathy and emotion-processing, antisocial and prosocial behaviour. These findings provide novel insight into the relationship between psychopathic traits and emotion-processing as well as antisocial and prosocial behaviour in the normal population, show the effectiveness of FFM traits in predicting psychopathy-related outcomes and highlight difficulties with regard to quantitative measures of attachment.