The Relationship between Individual Differences in the Responsivity of Rats to Stress and Intake of Alcohol

Abstract

Two groups of rats, equated for responsivity in an Open Area Test, were presented with a fluid choice situation modeled after Richter s "taste-threshold" technique. For Group S, the relative intracage position of the 2 choices, water and alcohol solution, was kept constant and the alcohol solution concentration was gradually increased each day. For Group R, the same series of alcohol solutions were utilized, but position and solution order were randomized. Significant and consistent positive rank-order correlations between individual differences in reactivity to the Open Area Test and alcohol solution intake were found for Group R, but not for Group S. This discrepancy is discussed in terms of the limitations imposed by Richter''s procedure as well as the possibility that the randomized procedure was inherently more stressful and this may have resulted in the selection of alcohol solutions as a learned adaptive response.