AA ascribes relapse to “triggers” like anger and resentment which induce cravings for relief, resulting in recurrence of addict thinking and behavior. Other powerful “triggers,” AA says, include reminders of past use. For an intravenous drug user a “trigger” could be the sight of a syringe, while for an alcoholic it might be a beer commercial.
What addicts call “triggers” scientists refer to as “cues,” powerful emotional memories of drug-taking. Dr. Anna Rose Childress, a psychiatrist at the University of Pennsylvania, has used PET scans in studying relapse triggers. During PET scans, radioactive elements1 are introduced into the brain to track cell processes,2 generating a three-dimensional image showing where the trace elements travel in the brain and how long they stay there.3 Dr. Childress reports that drug-taking cues cause the brain to release a small spurt of dopamine: “This increase in dopamine feels similar to a small dose of the drug itself,” she says. Some people report they can even taste the drug in the back of their throats, though they haven’t actually taken any.4 “They’re having a miniature high before they even get there,” Dr. Childress says. “It acts like a salty potato chip or the smell of the brownie across the room, the chocolate croissant in the window …. [I]t’s a primer, it’s a seductive pull.”5
To an addict, that “primer” prompts craving, a nearly instinctive cry for drugs. Dr. Nora Volkow, of the Brookhaven National Laboratory, performed brain scans of cocaine addicts while watching two videos: one of nature scenes, the other of people using cocaine. She found that dopamine increased in response to the drug-taking scenes in proportion to the subjective reporting of craving by the addicts. This illustrates the power of environmental cues and that they work unconsciously. Dr. Volkow says, “For these people, their lives and experiences have taught them that when they see others using cocaine, they’re probably about to get rewarded with drugs too. So even though they consciously knew they weren’t going to get cocaine after watching the video, their brains had learned to expect the reward.”6
Cue-related craving is tied to longer-lasting brain changes than were originally thought. For example, the hyperactivity of neurotransmitters associated with alcohol withdrawal can last as long as a year.7 Scientists suggest that relapse frequently happens because the spike in dopamine the addict brain experiences on seeing a “cue,” overpowers the planning and decision-making portion of the brain, the frontal cortex, where rational decision-making takes place.8 (For how this feels, click on Craving and Amnesia.) Addict’s thought-processes overstress the emotional short-term need of drug-induced relief from cravings over the rational long-term benefits of sobriety. Drug cues can rekindle that addict thinking no matter how long one has been sober. Cues operate swiftly and unconsciously, explaining why relapse happens so automatically that many who’ve had them say they were “struck drunk.”
Click here to return to the Questions About Addiction Menu.