Lithium effects on adjunctive alcohol consumption. II: Effects of adding concurrent shock

Abstract

Rats receiving chronic administration of lithium chloride (20 mEq/l) in their drinking water were tested for adjunctive alcohol (10% v/v) consumption in which temporally scheduled, noncontingent shock delivery was added following the establishment of food delivery-based adjunctive alcohol intake. The addition of shock to the eliciting schedule produced an initial reduction in alcohol consumption (Lithium subjects took longer to reach maximal suppression of drinking than did Controls), with a subsequent return to preshock levels for both groups. The reduction in alcohol consumption seen in control subjects following the discontinuation of food and shock delivery (extinction) was interpreted as suggesting that adding conflict/stress to established drinking conditions may facilitate subsequent extinction of that drinking behavior. Lithium subjects produced an initial suppression of drinking, with alcohol consumption returning to adjunctive levels by the end of the extinction series, suggesting that lithium decreases conflict/stress effects, that it impairs extinction processes, that it increases the reinforcing value of alcohol, or that it produces a combination of the three outcomes.