Lapses and reinstatement of heroin seeking in rats: comment on Leri and Stewart (2002).

Abstract

In an elegant series of experiments, F. Leri and J. Stewart (2002) report that exposure to heroin increases subsequent reinstatement responding if the animal has access to the drug lever during the lapse and if responding on the lever results in the presentation of conditioned cues. It is interesting that exposure to only these conditioned cues in the absence of heroin did not affect reinstatement responding on the following day. Although these are important experiments, the results should be interpreted with some degree of caution for several reasons. Nevertheless, the experiments described in this article represent the first attempt to address the effects of self-administered versus investigator-delivered heroin on subsequent reinstatement behavior. Future research should attempt to replicate these experiments taking these considerations into account.