Impairment of avoidance behavior following short-term ingestion of ethanol, tertiary-butanol, or pentobarbital in mice.

Acquisition of a shock avoidance task was impaired in mice after cessation of chronic consumption of ethanol, tertiary-butanol (t-butanol), or pentobarbital. The drugs were administered in liquid diets for 7 days after withdrawal of the drugs. The avoidance deficit was also observed 8 days after withdrawal from chronic pentobarbital. There was no apparent relationship between the avoidance deficit and physical dependence, as measured by a decrease in body temperature or convulsions on handling, since at 6 h after withdrawal only moderate withdrawal signs were seen in the mice consuming ethanol or t-butanol, and no withdrawal signs were seen in any of the mice at the time of avoidance testing. These results suggest that impairment of avoidance behavior after chronic exposure is a general effect of central nervous system depressants and, in the case of ethanol, is not due to the production of acetaldehyde.