A relationship between impulsivity and stronger stimulant and weaker sedative effects has implications for our understanding of risk factors for alcohol problems. Based on the present findings, the risk of alcohol problems linked to impulsivity (Verdejo-Garcia et al. 2008) may be due at least in part to enhanced stimulant and/or dampened sedative responses. This finding is in contrast to prior studies that have offered null and equivocal results relating impulsivity to subjective response (Corbin et al. 2008—unpublished findings; Magrys et al. 2013; Nagoshi et al. 1991; Rose and Grunsell 2008; Schuckit et al. 2012; Shannon et al. 2011; Yip et al. 2012). To our knowledge, among studies addressing relationships between impulsivity and subjective response, ours is the first to utilize data from IV administration. Use of IV ethanol infusion and clamping procedures may have facilitated observation of relationships between impulsivity and subjective response given the absence of potential confounds associated with oral administration (e.g., variable alcohol absorption and metabolism).
