Similar to the rewarding effects of natural stimuli, the rewarding properties of drug stimuli may also vary between adolescents and adults. Many of these ontogenetic studies have focused on nicotine and traditional stimulants, particularly cocaine, with findings to date generally showing enhanced preference for these drugs among adolescents relative to adults. In a study from our laboratory, adolescent male and female rats were found to exhibit significant nicotine-induced CPP to a relatively low dose of nicotine (0.6 mg/kg), whereas their adult counterparts failed to express CPP under these circumstances (Vastola et al., 2002). Adolescents have been reported to exhibit stronger nicotine-induced CPP than adults in other studies as well (e.g., Shram et al., 2006; Torres et al., 2008).
