The finding that measures of cognitive control (Stroop and flanker tasks) and reward processing (BART) were not related to impulsivity, risk behaviors, or externalizing symptoms was somewhat surprising given the central roles that they are assumed to play in these outcomes. It is important to keep in mind however that one measure of cognitive control (Stroop) was highly related to working memory and hence may not have contributed prediction beyond what it shared with that ability. Nevertheless, other research has also failed to find any relations between ECFs and early use of drugs (Nigg et al., 2004; Tarter et al., 2003), and research using proxies for risk taking such as the IGT also fail to find strong relations with ECFs in adolescents (Crone & van der Molen, 2004; Hooper et al., 2004). Results of the BART have to our knowledge only been correlated with drug use in small and older adolescent samples (Aklin et al., 2005; Lejuez, Aklin, Zvolensky et al., 2003).
