The consequences of different "lapses" on relapse to heroin seeking in rats

Although human studies have shown that a lapse, the first violation of abstinence, often induces resumption of drug taking, or relapse, it is not known what aspect of a lapse is critical to relapse or whether this phenomenon can be studied in other species. Rats were trained to self-administer heroin accompanied by a discrete light stimulus. After extinction, different groups experienced different "lapses." Twenty-four hours later, all groups received a test for relapse. It was found that a lapse during which heroin was self-administered, or was presented in close temporal contiguity with lever pressing, induced subsequent heroin seeking. Simple exposure to heroin, or to heroin-related stimuli, during the lapse had little effect on responding in the test for relapse.