The Validity of Primary and Secondary Subtypes of Psychopathy in Children and Adolescents
- Author(s): McKenzie, Meghan
- Advisor(s): Lee, Steve S
- et al.
Characterized by atypical behavioral (e.g., antisociality), interpersonal (e.g., egocentricity), and affective facets (e.g., low remorse), the phenomenological diversity of psychopathy likely consists of potentially etiologically distinct subtypes. Across community, clinic-referred, and adjudicated samples, anxiety and negative emotionality differentiated two subgroups of adolescents and adults with elevated psychopathic traits. In particular, secondary psychopathy was correlated with greater anxiety, negative emotionality, and stress reaction and lower control than primary psychopathy. Of central importance to the current study, primary and secondary psychopathy were conceptualized as being differentially sensitive to genetic and environmental influences. Specifically, primary psychopathy reflected more innate, genetically-based factors including affective disturbance (e.g., callousness) and minimal negative emotionality (e.g., anxiety), whereas secondary psychopathy was hypothesized to be an adaptation to environmental risk (e.g., maltreatment). However, empirical examinations of genetic and environmental contributions to subtypes provide inconsistent support for this theory, and knowledge about the mediational constructs and processes underlying the development of primary versus secondary subgroups of psychopathy is limited. Furthermore, anxiety-based distinctions of primary and secondary psychopathy have yet to be similarly evaluated in school-age children. This dissertation aimed to address these gaps directly. Using two independent, yet complementary, prospective longitudinal samples of 221 children with and without ADHD followed for two years (UCLA ADHD and Development Study) and a nationally representative sample of 15,701 adolescents followed prospectively across 14 years (National Longitudinal Study of Adolescent Health), we explored the validity of primary and secondary subgroups by examining their differential association with key correlates (e.g., maltreatment history, reactive aggression, antisocial behavior, delinquency, and emotional processing). Next, we tested whether individual differences in dimensions of temperament and self-regulation mediated predictions of primary and secondary psychopathy from a functional polymorphism regulating serotonin neurotransmission. Primary findings were three-fold. First, across both samples, secondary psychopathy demonstrated more anxiety and negative emotionality and engaged in greater total, nonviolent, and violent antisocial behavior than primary psychopathy. Second, secondary subgroups reported more diverse forms of childhood maltreatment relative to primary and comparison youth. Lastly, prosociality, but not negative emotionality, daring, or self-regulation, mediated predictions of psychopathy subgroups from 5-HTTLPR in childhood. In addition to providing support for primary and secondary psychopathy among children and non-adjudicated adolescents and adults, these findings also identify mediators of primary and secondary psychopathy. We discuss the utility of using population-based samples to examine individual differences within psychopathy, potential causal mechanisms that differentially contribute to psychopathy subgroups, as well as implications for tailored interventions targeting impairments associated with primary and secondary psychopathy.