Age and sex-differences in reward responding after punishment

Project Summary/Abstract A common intervention to prevent initial experimentation with drugs from continuing has been to inflict punishment, as a deterrent. But does punishment work? Studies in humans are surprisingly scant or biased, and rodent models offer the opportunity to test if punishment can deter future drug use, specifically during adolescence, which is when initial experimentation with drugs occurs. Preliminary data in rodent models show that male adolescent and adult rats equally suppress cocaine intake during punishment. However, the next day, when punishment is removed, adolescents resume cocaine intake to pre-punishment levels whereas adults continue to show suppressed intake. Punishment was in the form of contingent exposure to mild footshock during self-administration of cocaine. The goal of this proposal is to establish this phenomenon and its generalizability. Specifically, the first set of experiments will determine if the phenomenon is specific to males or if it generalizes to female adolescents; the second set of experiments will determine if the phenomenon is specific to cocaine or if it generalizes to a non-drug reward (sucrose). This small self-contained set of studies will establish the validity of this model and examine the generalizability of the effects across sexes and a non-drug reward. Results from these studies are significant, because they establish the futility of punishment as a deterrent for limiting future drug use in adolescents. This will prompt revisiting common parental and social interventions. Results from this study will also serve as the basis for a new line of research, aimed at understanding the neurobiological mechanisms underlying punishment resistance in adolescents, by focusing on brain circuits of punishment whose role in adolescent addiction has not been explored extensively.