The relationship between internalizing phenotypes and alcohol involvement is more nuanced. With few exceptions (Ning, Gondek, Patalay, & Ploubidis, 2020), internalizing has not been strongly linked to early alcohol involvement (e.g. initiation, intoxication) but has been prospectively linked to more severe alcohol engagement (e.g. AUD, relapse), with evidence that alcohol involvement may also potentiate internalizing symptoms (Bucholz et al., 2017; Elkins et al., 2006; Farmer et al., 2016; Flórez-Salamanca et al., 2013; King et al., 2020; McCabe, Brumback, Brown, & Meruelo, 2023; Menary, Corbin, & Chassin, 2017). Interestingly, some evidence suggests that internalizing symptoms and behavioral inhibition may initially protect against alcohol use in early adolescence (e.g. via reduced social use opportunities), but then confer risk for more rapid progression of use later when more opportunities to drink arise (Hussong, Ennett, Cox, & Haroon, 2017; Ning et al., 2020).
