Context is a trigger for relapse to alcohol

The environment in which alcohol consumption occurs may trigger later relapse in alcohol abusers. In this study we tested whether an alcohol-associated environment would induce alcohol-seeking behavior. Male rats (n=8) were trained to lever press for oral alcohol reinforcement in a distinctive context. Animals were water-restricted to encourage high ethanol intakes, to determine if the context may influence relapse at levels of ethanol consumption that are likely to alter hippocampal spatial functions. Responding was then extinguished in a different context. Placement of the rats back into the original context in which they self-administered alcohol induced a significant increase in lever press responding as compared to extinction levels of responding. The ability of the alcohol context to support alcohol-seeking behavior was maintained over three weeks, with no significant diminution, suggesting that regular consumption of moderate doses of ethanol during training (1.31 0.07 SEM g/kg per 1-hr session consumed on average over 15-20 days) did not affect the formation of the context-ethanol association. A second group of rats (n=6) was trained to lever press for sucrose reinforcement; this group also demonstrated context-dependent reinstatement, although the degree of reinstatement decreased over repeated tests, returning to extinction values after three weeks. These findings indicate that contextual conditioning has a long-term impact on ethanol-seeking behavior.