Resurgence of alcohol seeking produced by discontinuing... : Behavioural Pharmacology (original) (raw)

SHORT REPORTS

Resurgence of alcohol seeking produced by discontinuing non-drug reinforcement as an animal model of drug relapse

Department of Psychology, Utah State University, Logan, Utah, USA

Correspondence and requests for reprints to Christopher A. Podlesnik, Department of Psychology, 2810 Old Main Hill, Utah State University, Logan, UT 84322, USA

E-mail: [email protected]

Sponsorship: This research was funded by National Institute on Alcohol Abuse and Alcoholism, grant number AA013576.

Received 12 January 2006 Accepted as revised 15 May 2006

1Studies included in these calculations are indicated in the reference section by the numerical superscripts for reinstatement by alcohol priming2, alcohol cues3, within-session presentations of alcohol4, and foot shock5. Estimates of mean response rates during reinstatement conditions were obtained for individual groups of rats from the figures of previous studies. Groups of rats from previous studies were included if they assessed only the effects of alcohol priming, alcohol cues, within-session alcohol presentations, or foot shock. Drug-priming groups were included given reinstatement by intraperitoneal injections of alcohol or orally administered alcohol (gavage). Drug-cue groups were included given presentations of olfactory discriminative stimuli and visual stimuli paired with ethanol delivery during baseline because most studies on the effects of drug cues on reinstatement have been examined this way. Within-session alcohol-presentation groups were included if alcohol was presented with the same stimuli during reinstatement as during baseline conditions. Finally, foot-shock groups were included given presentations of foot shock occurred in the absence of alcohol or drug cues. In addition, if reinstatement was assessed under multiple conditions (e.g. multiple priming doses, durations of exposure to stress), only the group with the highest response rate during the reinstatement condition was included.

Abstract

Findings from basic behavioral research suggest that simply discontinuing reinforcement for a recently reinforced operant response can cause the recurrence (i.e. resurgence) of a different previously reinforced response. The present experiment examined resurgence as an animal model of drug relapse. Initially, rats pressed levers to self-administer alcohol during baseline conditions. Next, alcohol self-administration was discontinued and non-drug reinforcers (food pellets) were presented contingent on an alternative response (chain pulling). Finally, when the non-drug reinforcer was discontinued, alcohol seeking recurred even though alcohol was still unavailable for lever pressing. These results suggest that simply discontinuing non-drug reinforcement for a behavior may be sufficient to produce relapse to drug seeking. The resurgence procedure could provide a method to examine environmental, pharmacological, and neurobiological factors that lead to relapse following the loss of a non-drug source of reinforcement.