The Development of Impulsivity and Sensation Seeking: Sources of Between- and Within-Individual Differences Over Time and Across Sex

Criminological theories have long incorporated personality traits as key explanatory factors and have generally relied on assumptions of trait stability. However, growing evidence from a variety of fields including criminology, psychology, and neurobiology is demonstrating that personality traits are malleable over the life-course, and substantial individual variation exists in the developmental patterns of personality traits over time. This research is forcing criminologists to consider how and why “enduring” individual characteristics may change over the life course in ways that are meaningfully related to offending. Two traits that have been consistently linked to offending and conflated in key criminological theories (i.e. Gottfredson and Hirschi’s self-control theory), impulsivity and sensation seeking, have recently been shown to be independent personality traits with different normative maturational timetables and biological underpinnings. This dissertation extends this work by examining developmental patterns of impulsivity and sensation seeking and social sources of variation in these traits with the Family and Community Health Survey, a longitudinal data set that consists of approximately 900 African American youth and their families followed from late childhood to their late-twenties. Multiple longitudinal modeling methods are employed (hierarchical linear modeling and group-based trajectory modeling) to address this research agenda. Results from this dissertation lead to four broad conclusions. First, and in support of existing research, there is substantial variability in developmental trajectories of impulsivity and sensation seeking. Average developmental trajectories of these traits greatly mask the degree of individual variability in developmental patterns that exists. Second, social factors are significantly associated with levels of impulsivity and sensation seeking. Socio-environmental experiences characterized by hostility and unsupportiveness are generally associated with elevated levels of impulsivity and sensation seeking while socio-environmental experiences characterized by warmth and supportiveness are associated with lower levels of impulsivity and sensation seeking. Third, sex differences in developmental patterns of impulsivity are nonexistent while sex differences in developmental patterns of sensation seeking are significant. Finally, with few exceptions, predictors of trait levels operate in a general fashion such the same factors typically explain both male and female trait levels and produce similar effects on impulsivity and sensation seeking.