Racial Differences in the Development of Impulsivity and Sensation Seeking from Childhood into Adolescence and Their Relation to Alcohol Use

African American adolescents have lower levels of alcohol involvement than European American adolescents: they are more likely to abstain from alcohol (Pemberton, Colliver, Robbins & Gfroerer, 2008), drink alcohol less frequently, and engage in less heavy drinking (Johnston, O’Malley, Bachman, & Schulenberg, 2010). Relatively little research has been conducted to move beyond these broad epidemiological findings. The goal of the current study was to examine two facets of disinhibition, sensation seeking and impulsivity, that may help explain these racial differences. Disinhibition and Alcohol Use Disinhibition is a broad term that has been used to describe different constructs that predispose individuals to act rashly or impulsively. A large body of research has linked aspects of this construct to the onset and escalation of alcohol use and to alcohol use disorders in adults (see reviews: Dick, Smith, Olausson, Mitchell, Leeman, O’Malley, & Sher, 2010; de Wit, 2008; Lejuez, Magidson, Mitchell, Sinha, Stevens, & de Wit, 2010) and to a variety of risk-taking behaviors in adolescence (e.g., Kiriski, Vanyukov, & Tarter, 2005; Elkins, King, McGue, & Iacono, 2006; MacPherson, Magidson, Reynolds, Kahler, & Lejuez, 2010). Recent work has shown that specific facets of disinhibition relate to different aspects of alcohol use and risk-taking behaviors in adults (Smith, Fischer, Cyders, Annus, Spillane, & McCarthy, 2007; Fischer & Smith, 2008; Cyders, Flory, Rainer, & Smith, 2009) and children/adolescents (Zapolski, Zapolski, Stairs, Settles, Combs, & Smith, 2010), highlighting the importance of examining the association between specific facets of disinhibition and alcohol use. Changes in Disinhibition across the Lifespan Until recently, personality characteristics were thought to be stable across the lifespan. However, increasing evidence shows that levels of personality characteristics change considerably across the lifespan, with the largest changes occurring in late adolescence (see Roberts, Walton, & Viechtbauer, 2006, for a meta-analysis). Disinhibition has been shown to peak in adolescence and to decline in adulthood (Blonigen, Hicks, Krueger, Patrick, Iacono, 2006), paralleling the “maturing out” of heavy alcohol use in adulthood (Littlefield, Sher, & Wood, 2009). Although the majority of this research has focused on the transition from adolescence into adulthood, differences in disinhibition levels also exist between children and adolescents. Steinberg and colleagues (2008) examined cross-sectional differences in sensation seeking and impulsivity in individuals aged 10–30 and found the highest levels of sensation seeking in 12–15 year olds; in contrast, impulsivity declined steadily from ages 10 to 30. These findings suggest that different facets of disinhibition may show differing developmental trajectories in adolescence. Individual differences in these changes have also been found suggesting that the “maturation” seen in late adolescence is highly variable across individuals and is predictive of risk-taking outcomes (e.g., Johnson, Hicks, McGue, Iacono, 2007; Monahan, Steinberg, Cauffman, & Mulvey, 2009). Racial Differences in Disinhibited Personality Characteristics Racial differences in disinhibition have been little studied, and available findings present a complex picture. Importantly, in a review of racial differences in risk factors for adolescent drinking and drug use, Wallace and Muroff (2002) omitted any discussion of disinhibition. Cross-sectional research suggests that European American youth have higher levels of sensation seeking than African American youth (e.g., Hoyle, Stephenson, Palmgreen, Lorch, & Donohew, 2002; Russo, Stokes, Lahey, Christ, McBurnett, Loeber, Stouthamer-Loeber, & Green, 1993). Similarly, Crawford and colleagues (2003) found that European American children had higher levels of and sharper increases in sensation seeking than other ethnicities over a two-year period in middle school. Research also suggests that sensation seeking may relate more strongly to risky behaviors among European Americans than among African Americans. For example, Cooper and colleagues (2003) found sensation seeking related to a general factor of problem behavior (i.e., risky sexual activity, substance use, delinquency, academic underachievement) for European American but not for African American adolescents. Additionally, a meta-analysis (Hittner & Swickert, 2006) found that sensation seeking related more strongly to alcohol use in studies having a higher percentage of European Americans, suggesting that sensation seeking may relate more strongly to alcohol use for this racial group. Research on impulsivity paints a different picture. Although there is little research on this topic, studies of children with Attention Deficit Hyperactivity Disorder, a disorder with a high degree of impulsivity, have found that African American children have higher levels of impulsivity than European American children (e.g., DuPaul, Anastopoulos, Power, Reid, Ikeda, & McGoey, 1998; Bussing et al., 2008). The relative lack of research in this area has resulted in a lack of understanding about why these racial differences may exist, whether they exist in non-clinical populations, and the role impulsivity plays in racial differences in alcohol use. Prospective studies are needed to examine changes in disinhibited personality characteristics between African Americans and European Americans. Aims of the Research The current study had three aims. First, we examined change in sensation seeking and impulsivity from mid-childhood into mid-adolescence. Based on previous research, we hypothesized that sensation seeking would increase and that impulsivity would decrease over time. Second, we hypothesized that individual differences in the rate of change in disinhibition would relate prospectively to later alcohol use. For example, while sensation seeking may increase on average over time, individuals with sharper increases in sensation seeking were hypothesized to drink alcohol more frequently than those with smaller increases. The third aim of the study was to examine racial differences in both initial levels and rates of change in sensation seeking and impulsivity. Within this aim we examined the possibility that sensation seeking may mediate the association between race and alcohol use. Specifically, African Americans may have lower levels of sensation seeking which could partially explain their lower subsequent levels of alcohol use. We did not hypothesize a mediational pathway through impulsivity. We also tested whether the association between sensation seeking/impulsivity and alcohol use differed across race. We hypothesized that sensation seeking/impulsivity would relate more strongly to alcohol use for European Americans than for African Americans.