Ethanol blockade of context change effects.

Rats were trained to run to four baited arms of an eight-arm radial maze. Half the subjects were trained in one context, half in another. Additionally, half of each of these groups received alcohol (1.5 g/kg ethanol) pretreatment while the rest were given saline. Following attainment of criterion, the context conditions were reversed for all subjects, but the drug assignment remained in force. Saline-injected rats were strongly disrupted by the train-test context shift. Alcohol-injected subjects were unaffected by the change in setting. Alcohol seems either to diminish the contextual composition of memories or to block the reaction to environmental mismatch during testing.