The Effects of chronic alcohol consumption or thiamin deficiency on radial-arm maze performance in the rat

Experiment 1 tested the hypothesis that chronic consumption of ethanol, in the presence of good nutrition, is associated with impairments in memory. Rats were fed a vitamin-fortified ethanol-Sustagen diet with 35% ethanol-derived calories for 150 days. Two control groups were used. The first was pair fed a Sustagen mix in which sucrose had been substituted for ethanol. The second control group received ad lib access to standard laboratory chow and water. All animals were then placed on the chow and water diet for six weeks prior to testing in an eight-arm radial maze. There was a significant, but modest, difference between groups in the number of trials to reach a criterion level of seven correct from the first eight choices and all eight correct in ten choices. However, there were no differences between the groups when delays (0, 5, 20, 60, 120 and 240 minutes) were imposed between the 4th and 5th choices. In Experiment 2, a thiamin-deficient group was compared with pair-fed and ad lib control groups on the same task. The thiamin-deficient group took more trials to reach criterion but the groups did not differ in the delay testing phase. The results are discussed in the context of reference/working memory distinctions, and the literature on remediation of cognitive deficits associated with alcoholism.