Reinstatement of ethanol tolerance: The role of the context

Abstract

The reinstatement of the ataxic effect of ethanol was studied in three groups of rats. All subjects received a visual stimulus (i.e., conditioned stimulus, CS), paired in repeated occasions with the effect of an ethanol dose (i.e., unconditioned stimulus, US). Then, all subjects received unpaired presentations of the CS aimed at extinguishing the CS-US association formed in the previous phase. After extinction, one group received an unpaired presentation of the US in the extinction context, a second group received an unpaired presentation of the US in a new context, and a third group did not receive US presentations. Finally, the tolerance response to the ataxic effect of ethanol was assessed in reacquisition trials. The results show that a nonsignaled administration of ethanol is efficient in reinstating an extinguished tolerance response, and that the context in which the ethanol is administered determines the magnitude of the reinstated conditioned response. This study, together with previous data, helps to understand the mechanisms of relapse in cue exposure therapies.