Measuring ethanol-seeking behavior: the effect of using repeated extinction trials

The development of a reliable measure of the level of ethanol-seeking behav ior in an animal model is important to understanding the concept of craving . However, most existing models do not allow for the separation of the beha vior associated with obtaining ethanol from that involved in consumption of ethanol. In this study, we determined the ability of repeated, single-sess ion extinction tests in an appetitive and consummatory procedure of ethanol self-administration to assess the level of seeking behavior. The findings indicated that there were no major effects of previous extinction trials on later trials, when there were at least four reinforced sessions between te sts. During reinforced sessions, the rats were consuming an average of 0.80 g of ethanol per kilogram of body weight in less than 20 min from a sipper tube. In addition, the amount of extinction responding was found to be sim ilar to a previous measure of the appetitive strength of ethanol by using a breakpoint procedure. This method of repeated extinction tests seems to be valuable for examining the effects of pharmacological treatments that migh t alter ethanol seeking. (C) 2001 Elsevier Science Inc. All rights reserved .