Classical conditioning in humans: nicotine as CS and alcohol as US

Abstract

Animal studies suggest that drug effects can act as conditioned stimuli for various unconditioned stimuli including the effects of other drugs. The current study investigated drug-drug conditioning in human subjects. Sixteen subjects were given subcutaneous injections of either nicotine or saline before consumption of an afcohoiic or soft drink in each of eight sessions. Across sessions the content of the injections was established as a reliable predictor of the alcoholic content of the drink. Physiological, subjective, and behavioural responses to the injections were used as indices of conditioning.Skin conductance measures obtained following the injections changed across trials in a way consistent with a conditioned response though patterns of change on cardiac inter-beat interval were less clear. However, neither behavioural nor subjective measures showed conditioning effects. In view of the number of variables studied the evidence for the development of conditioned responding on physiological measures must be suspected of being a type 1 error and is in need of replication. Subjects' reports revealed that nicotine and saline injections were difficult to discriminate. This would have weakened conditioning effects. Suggestions are made for improvements in the design of future studies of drug-drug conditioning in human subjects.

Nicotine does not produce state-dependent effects on learning in a Pavlovian appetitive goal tracking task with rats

“…Until unambiguous evidence demonstrating the exclusive role of operant contingencies is available, we prefer to pursue this avenue of research from a Pavlovian conditioning framework for the mere utilitarian reason that this approach leads to novel and potentially important experiments that could elucidate factors contributing to drug addiction. That is, perhaps the abuse liability of nicotine-containing products could be affected by conditioned associations in which nicotine is an interoceptive cue for other appetitive USs [7,9,34]. Such evidence has been found in humans using diazepam [1] and ethanol [31] as the interoceptive cue.…”

Nicotine as a conditioned stimulus: Impact of attention-deficit/hyperactivity disorder medications.

“…Indeed, this framework is the most commonly used to study the potential conditioning processes contributing to nicotine use (see , for a review). Research from our laboratory and others has extended this conceptualization to include nicotine as an interoceptive CS (Besheer, Palmatier, Metschke, & Bevins, 2004;Bevins, Penrod, & Reichel, 2007;Clements, Glautier, Stolerman, White, & Taylor, 1996;Murray & Bevins, 2007;Troisi, 2006;Wilkinson et al, 2006). In our research, to train nicotine as a CS, rats had intermittent access to sucrose on nicotine sessions; on intermixed saline sessions no sucrose was present.…”

Interoceptive conditioning in rats: Effects of using a single training dose or a set of 5 different doses of nicotine

“…(Koob, 2004). Continued efforts to better understand the role of learning involving interoceptive stimuli are needed for a more comprehensive theory of drug addiction (Bevins et al , 2011; Bevins et al , 2004; Paulus and Stewart, 2013; Wise et al , 2008) and improved intervention and prevention approaches (Alessi et al , 2002; Clements et al , 1996; Glautier et al , 1996). …”

“…Elucidating the contribution of interoceptive conditioning to drug addiction is critical to advance our understanding and treatment of addiction (Alessi et al , 2002; Bevins et al , 2012; Clements et al , 1996; Glautier et al , 1996; Wise et al , 2008). One preclinical model used to study nicotine interoceptive conditioning is the discriminated goal-tracking task with rats (Besheer et al , 2004; Charntikov et al , 2012; Murray and Bevins, 2007a, b; Polewan et al , 2013; Reichel et al , 2010; Struthers et al , 2009; Wilkinson et al , 2006).…”