Chasing the memory, not the high
- April 21, 2020
- UCI cognitive scientist says episodic memory, more than compulsive behavior, could be to blame for relapses among those addicted to drugs and/or alcohol
Addiction to drugs and/or alcohol is a problem that affects millions of Americans - yet one for which treatment has advanced very little for decades, says UCI cognitive sciences professor Aaron Bornstein (pictured). And with the National Institute on Drug Abuse reporting that 40- to 60-percent of people in recovery relapse, something’s gotta give.
“I think we’ve been looking at the model for addiction wrong,” he says. In an article published online in Neuropsychopharmacology, he and co-author Hanna Pickard, Bloomberg Distinguished Professor of philosophy and bioethics at Johns Hopkins University, present a novel theory that focuses on memory, not compulsion, as the driving factor behind addictive behavior.
“If you speak to an addict,” Bornstein says, “you will often hear stories of the first time they remember really enjoying their drug of choice. These memories will be rich, vividly detailed - what music was playing, what color shirt their friend was wearing, and so on.” Bornstein and Pickard reasoned that these memories might themselves be driving the choice to use drugs again, in the future.
Bornstein, who specializes in memory and decision making, recently earned a Rising Star Award from the Association for Psychological Science. He teamed up with Pickard - a philosopher and bioethicist with years of clinical experience - to understand how computer-simulated laboratory experiments could help answer what Pickard calls “The Puzzle of Addiction” - how we can explain why addicts persist in using drugs despite increasing negative consequences that might, to an outside observer, appear to outweigh any and all benefits to consumption.
“My previous work has shown that episodic memory of rewarding past experiences guides our decisions in the present - sometimes to our detriment,” he says. “And, when those rewarding experiences come back to mind, they might drive us to re-live them - regardless of cost.” This idea could explain why people keep using drugs despite having repeated negative experiences. It might also explain how people can relapse, even after years without using. Put another way, the drug may have disappeared from their lives, but the memories always remain.
This is a different way of looking at addiction than is typical in contemporary research. Most work on substance abuse uses rodents as models, because a great deal can be learned about the specific neural circuits that underlie a behavior, Bornstein explains. But rodent addiction in the lab differs from the human experience in several important ways.
“For one, humans tend to know what they’re getting in to when they take a drug for the first time. Someone probably tells the person what they’re taking and they’re probably with friends or in an environment with lots of details that can define that moment in time,” he says. Conversely, an animal is often just hitting a lever in a box and has no idea what’s coming or how to make sense of it. So even if there is a memory of that experience, it might not be tied to the sensation they’re feeling in the same way. This may be part of the reason that addiction research tends to think of drug-seeking behavior as purely compulsion - that’s all there is in rodents, he says.
“A recovering addict may know the consequences of using again, but something as seemingly innocuous as a social cue – like seeing a friend they’ve used with in the past – can bring back those past experiences, and might be enough to cause a relapse, despite the consequences,” he says. “This richness of memory is exactly why it can be so dangerous.”
They reason that there’s something more happening beyond a compulsive, habit-like response. And unlocking the solutions to this puzzle may help clear the way to new treatments.
“Once we understand that the drug use and relapse may sometimes be caused by the impact of episodic memories of early drug experience on present decisions, we can see a new target for intervention,” says Pickard. “Drug memories can’t be erased, but their power can be diminished, if other things that a person values can be simultaneously brought to mind when they are faced with a decision to use.”
This new model suggests that treatment for addiction may need to focus on strengthening existing and creating new associations between drug cues and drug-inconsistent rewards, rather than breaking learned associations between drug cues and drug rewards - which is a common goal of many other treatments under development today. The researchers are pursuing these questions using tools from philosophy, the laboratory and the clinic to try and understand both what drives people to remember these early drug experiences, and how to guide them to build new experiences and memories that can help them achieve the life they want to live.
-Heather Ashbach, UCI Social Sciences