The normal developmental insensitivity of adolescents to the intoxicating effects of alcohol may not only interact with genetically related insensitivities but may also be exacerbated by the induction of chronic tolerance to alcohol, with human survey data reporting a high prevalence of tolerance among adolescent drinkers (Grant et al., 2007) and basic science studies suggesting that under some circumstances, adolescents develop at least as much chronic tolerance with repeated exposures to alcohol as do adults (Varlinskaya & Spear, 2007). Work in laboratory animals suggests that a history of prior stressor exposure may further lower sensitivity to the intoxicating properties of alcohol (Doremus-Fitzwater et al., 2007). Thus, typical adolescent insensitivities to the aversive and intoxicating effects of alcohol may combine with alcohol insensitivities induced by genetic history, prior stressors, and tolerance associated with repeated use to potentially serve as triple or quadruple “whammies,” thereby promoting high levels of alcohol use--such as might be seen when individuals with a family history of alcoholism and living in stressful circumstances begin to drink early and persistently in adolescence (see Spear, 2010, for further discussion).
