Early learning and retention of a conditioned taste aversion

Abstract

Weanling rats were trained on a taste aversion task and tested 60 days later using the single bottle and preference methods for assessing the retention of a taste aversion, and a competitive situation in which the CS was eventually substituted for plain water. Only the competitive situation showed the effects of the early taste aversion training. The results are discussed in terms of the conditioning and reactivation of adrenocortical steroid elevations and how these might affect subsequent retrieval.

Long-term retention of a conditioned taste aversion in preweanling and adult rats

“…Requests for reprints should be sent to Norman E. Spear, Department of Psychology, State University of New York at Binghamton, Binghamton, New York 13901. these procedures suggest that, by 18 days of age, rat pups have attained adult levels of retention for a taste-illness association. In contrast to the findings of Campbell and Alberts (1979), Ader and Peck (1977) and Peck (Note 1) have reported relatively poor retention of all early (Zl-day-old rat pup) taste-illness experience over a 6O-day interval. These studies employed cyclophosphamide as the US and used both single-bottle and preference tests.…”

Learning and retention of sucrose taste aversion in weanling rats

“…Klein,Mikulka,Domato,and Hallstead (I 976) reported that rats, poisoned at 28 days of age, showed reliable aversion effects 1 day or 28 days later. Conversely, Ader and Peck (1977) found no reliable evidence of retention of taste aversion in weanling rats tested in isolation 60 days after aversion training. Only Klein et al (1976) have reported wean lings' retention of taste aversion at two independently assessed temporal intervals.…”

“…In Experiment 2, 80 rat pups, 21 days old, drank 9% sucrose and received an injection of LiCI (3.0 mEq) or distilled water and then were tested for taste aversion 24, 48, 72, or 168 h later. Aversion effects were reliable at each retention interval; the magnitude of aversion was invariant across intervals.Recent studies of taste aversion learning have shown that when the conditions of training and testing are appropriate, young rats 22 to 29 days old learn to inhibit consummatory responding toward a taste stimulus that previously accompanied toxicosis (e.g., Ader & Peck, 1977;Baker, Baker, & Kesner, 1977; Grote & Brown, 1971 b; Klein, Domato, Hallstead, Stephens, & Mikulka, 1975). However, Baker et aL (1977) and Klein et al (1975) have indicated that although taste aversion effects were demonstrable with young rats, these effects seemed more labile than they appeared to be for older rats, 80 days of age.…”

“…Each pup received nine 1-h test periods, one period every 24 h. The measure of performance was the amount drunk (in milliliters) from each bottle, as calculated by the difference in the bottle's weight between pre-and posttest weighings. A sucrose preference index (Ader & Peck, 1977) was calculated for each test day: sucrose intake relative to total fluid intake, Suc/(Suc + Hoh) X 100.To evaluate the effects of the injection conditions on the growth of the young animals, each pup was weighed daily throughout the experiment. The weight data showed that all rat pups lost weight (range: .5-4.0 g) on the first 2 days following separation from the darn.…”

“…Each pup received nine 1-h test periods, one period every 24 h. The measure of performance was the amount drunk (in milliliters) from each bottle, as calculated by the difference in the bottle's weight between pre-and posttest weighings. A sucrose preference index (Ader & Peck, 1977) was calculated for each test day: sucrose intake relative to total fluid intake, Suc/(Suc + Hoh) X 100.…”