Conditioned taste aversion learning

Abstract

Drugs of abuse are typically discussed in terms of their rewarding effects and how these effects mediate drug taking. However, these drugs produce aversive effects that could have an important role in the overall acceptability of a drug and its likelihood of being self-administered. Rewarding and aversive effects, then, could be interpreted as separate behavioral effects, with the balance of the two determining overall drug acceptability. Interestingly, the role of aversive effects on drug acceptability in the self-administration preparation has received limited attention in this context. This chapter examines the aversive effects of drugs and discusses their role in drug taking. If these aversive effects serve a protective function, manipulations that alter or decrease these effects could have implications for drug taking. Several factors have been reported to alter conditioned taste aversion (CTA) learning, a preparation used in the assessment of the aversive effects of drugs in general. Two of these factors, drug history and strain, are reviewed here. By reviewing these, we intend to demonstrate the protective nature of aversive effects in the initiation and escalation of drug taking and to provide evidence that reductions in aversive effects could produce changes in patterns of drug self-administration that could lead to an increased vulnerability to abuse drugs by altering the reward-aversion balance. The aim of this chapter is not to question the importance of rewarding effects in self-administration but rather to provide evidence that aversive effects are an important factor that needs to be considered in discussions of drug-taking behavior.

Schedule-induced polydipsia as a model of compulsive behavior: neuropharmacological and neuroendocrine bases

“…These two inbred strains have been extensively used as animal vulnerability models for drug abuse. In brief, LEW animals (compared to the F344 rats) typically displayed greater acquisition of self-administration of several drugs of abuse, such as morphine and other opiates, nicotine, alcohol, and cocaine (for reviews, see Kosten and Ambrosio 2002;Davis and Riley 2010). The differences between these two strains in the SIP task also correlated with other indices of stress.…”

Conditioned taste aversion, drugs of abuse and palatability

“…Beginning in the late 1960s, it was discovered that drugs of abuse could suppress intake of an associated taste CS, the traditional behavioral hallmark of CTAs (e.g., Berger, 1972; Cappell & LeBlanc, 1971; Cappell, LeBlanc, & Endrenyi, 1973; Carey, 1973; Davison & House, 1975; Goudie, Dickins & Thornton, 1978; Kay, 1975; Le Magnen, 1969; Nachman, Lester, & Le Magnen, 1970; Nathan & Vogel, 1975; Riley, Jacobs, & LoLordo, 1978; Vogel & Nathan, 1975; for reviews see Davis & Riley, 2010; Hunt & Amit, 1987; Riley, 2011). Complicating the straightforward interpretation that drugs of abuse induce CTAs is the simple fact that the same drugs are self-administered by humans and other animals and support conditioned place preference learning (see Bardo & Bevins, 2000; Carr, Fibiger, & Phillips; 1989; Jaffe, 1970; Schechter & Calcagnetti, 1993; Schuster & Thompson, 1969; Tzschentke, 1998, 2007; van Rees, 1979; Weeks, 1962).…”

“…The nature of the US responsible for CTAs induced with drugs of abuse has been debated for many years (e.g., Davis & Riley, 2010; Gamzu, 1977; Goudie, 1979; Grigson et al, 2009; Hunt & Amit, 1987; Parker et al, 2009). One approach to this issue might involve the use pharmacological treatments, central or systemic, to investigate the influence of blocking specific properties of drug of abuse USs on CTA acquisition.…”

Once is too much: Conditioned aversion develops immediately and predicts future cocaine self-administration behavior in rats.

“…Following repeated daily pairings, rats come to avoid intake of the saccharin cue in anticipation of drug availability relative to intake by saccharin-saline paired controls. This paradigm has, in fact, been studied for decades (Cappell & LeBlanc, 1971; Le Magnen, 1969), but was quickly interpreted as a conditioned taste aversion akin to that induced by the illness-inducing agent, LiCl (Davis & Riley, 2010; Lester, Nachman, & Le Magnen, 1970), and, as such, as evidence for aversive drug properties. We reinterpreted these data and hypothesized that rats avoid intake of the saccharin cue, at least in part, because the taste cue pales in perceived value relative to the potent drug of abuse expected in the very near future (Grigson, 1997).…”