The role of orosensory stimuli from ethanol and blood-alcohol levels in producing conditioned taste aversion in the rat.

A taste-aversion paradigm was used to demonstrate that aversive consequences accompany the rapid oral ingestion of 5% (v/v) ethanol solutions. The learned taste aversion resulted from five 10-min self-administrations of alcohol mixed with an originally preferred flavor at a dosage of 1.69 g alcohol/kg body weight/day. In contrast, when the consumption of the alcohol solution was distributed throughout the day, a conditioned aversion was not obtained. This outcome was observed even though the distributed drinking animals were exposed to more orosensory stimuli and ingested more g/kg than the 10-min animals. The observation that those animals that drank their daily fluid in 10 min demonstrated higher peak blood-alcohol levels than the distributed animals supports the conclusion that a centrally mediated aversive state of inebriation must be present to produce a conditioned aversion.