Differential effects of fluid deprivation on the acquisition and extinction phases of a conditioned taste aversion

Abstract

Previous work has shown that the rate of extinction of a conditioned taste aversion by a male (but not a female) rat is affected by the state of fluid deprivation. In the present study. adult male rats were either fluid deprived or nondeprived during acquisition of the conditioned taste aversion and then either fluid deprived or nondeprived during its extinction. The males that were fluid deprived during extinction showed a faster. female-like rate of extinction regardless of the deprivation state during acquisition. These results were related to previous work showing that the rate of extinction of a conditioned taste aversion is dependent on levels of testosterone.Chambers and Sengstake (1976) have found that males extinguish a conditioned taste aversion more slowly than females. This sexual dimorphism has been shown to be concurrently dependent on testosterone (Chambers, 1976). When males are castrated, they exhibit a fast, female-like rate of extinction. When females and castrated males are given testosterone supplements, they exhibit a slow, male-like rate of extinction. Thus, testosterone increases the length of time the animal takes to extinguish the aversion. If testosterone is not present, the expression of the slower rate of extinction is blocked and the males act like females.The sexual dimorphism is also blocked when rats are fluid deprived. The rate of extinction seen in females is unaffected by fluid deprivation, but the males, which normally show the slower rate of extinction, will change to the faster, female-like rate if they are fluid deprived. This increased rate of extinction in the deprived male is not due to forced drinking of the conditioned substance , since water was also available during behavioral testing (Sengstake, Chambers, & Thrower, 1978).The behavioral similarity between castrated males and fluid-deprived males earlier led us to hypothesize that the effects of fluid deprivation on the rate of extinction occur through a testosterone-dependent mechanism, a hypothesis that was supported by the demonstration that injections of testosterone propionate blocked the effects of fluid deprivation on the rate of extinction in the male rat (Sengstake et aI., 1978).A change in the rate of extinction can be a function of events occurring during the acquisition of the aversion or events occurring during the extinction of the aversion.We would like to express our thanks to Diana Hainline for her technical assistance during the collection of these data. Requests for reprints may be addressed to the authors at Department of Psychology. Portland State University, P.O. Box 751, Portland, Oregon 97207 .Copyright 1979 Psychonomic Society, Inc. 85Chambers and Sengstake (1979) have shown that testosterone slows the rate of extinction by altering the extinction (but not the acquisition) process in some unspecified way. The slower rate of extinction of the conditioned taste aversion; the presence , or absence, of testosterone during the acquisition of the aversion has no effect on the rate of its extinctio...

Strain-dependent sexual dimorphism in the extinction of conditioned taste aversion in mice

“…Although acquisition of CT A would occur under fluid-deprived conditions, the protocol allowed the extinction phase of the experiment to be conducted under nondeprived conditions. Sengstake and Chambers (1979) had observed that a similar paradigm was as effective in producing the sexual dimorphism in extinction rate as was a paradigm in which both acquisition and extinction were conducted under nondeprived conditions. tion, there was a significant Sex by Day interaction [F(4,IOO)=3.74, p < .01].…”

“…This experiment was designed to follow the protocol of previous studies which induced CTA under nondeprived conditions (Chambers, 1976;Chambers & Sengstake, 1976, 1978Sengstake & Chambers, 1979). A comparison of resistance to extinction was made between two genotypes of mice of both sexes.…”

“…Sexual dimorphism is most reliably observed when fluids are provided ad lib during the extinction process (Chambers & Sengstake, 1976; Sengstake & Chambers, 1979; Sengstake, Chambers, & Thrower, 1978). Fluid deprivation results in decreased resistance to CTA extinction, presumably due to decreased levels of circulating testosterone.…”

Age differences in (±) 3,4‐methylenedioxymethamphetamine (MDMA)‐induced conditioned taste aversions and monoaminergic levels

“…In both of these assessments, there was no difference in the overall pattern of responding between the deprivation conditions with adolescent animals displaying attenuated aversions in comparison to the adults (Hurwitz et al, 2012). Further, the age difference in the aversive effects of MDMA was still evident in the two-bottle test, an assessment that is less influenced by fluid deprivation given that it does not require animals to consume saccharin when the water choice is freely available (Grote & Brown, 1971;Sengstake and Chambers, 1979). Although motivation to drink may not have been a contributing factor, it is nonetheless possible that the fluid deprivation schedule employed was more stressful in the adolescent subjects relative to their adult counterparts.…”

Sex Differences in Cue Competition Effects With a Conditioned Taste Aversion Preparation

“…For instance, sex differences in conditioning acquisition have been observed in fear conditioning (see above) or eye-blink conditioning (apparently being stronger in females; for instance see Waddell et al, 2008) but not in other models such as conditioned taste aversion (CTA; for instance see Randall-Thompson and Riley, 2003;Angulo and Arévalo-Romero, in press;Jones et al, 2006;Pittman et al, 2008;Rinker et al, 2008). Finally, within the same experimental model, specifically CTA, sex differences might be observed in some effects as extinction (e.g., Chambers and Sengstake, 1979;Sengstake and Chambers, 1979) or latent inhibition (e.g., Nofrey et al, 2008;Quinlan et al, 2010) but not in others as acquisition (e.g., Randall-Thompson and Riley, 2003;Jones et al, 2006;Pittman et al, 2008;Rinker et al, 2008). According to the evidence, thus, it seems reasonable to assume that the hypothesis of a general sex difference for certain conditioning effects will require a confirmation from studies using different experimental preparations.…”