Disrupting Contextual Memories Induced by Drugs of Abuse Alleviates Motivational Withdrawal

Memory plays a major role in the development of addiction. Places where drugs are experienced become associated with the effect of the drugs, and re-encountering those places brings back the memory of being high, precipitating craving and relapse.

Memories can be temporarily fragile when recalled or reactivated, but over the course of this phase, called reconsolidation, they again become strong and resilient to disruption. The initial temporal window of fragility offers an opportunity to block the reconsolidation process and therefore weaken or eliminate the memory. Such an approach can be used to decrease strong associations that contribute to pathologies such as drug addiction responses.

Taubenfeld et al., in a study published this week in Proceedings of the National Academy of Sciences (PNAS), and supported by the Philoctetes Center, trained rats to experience the effect of morphine in a given context. After a few days, the rats developed a preference for that context and appeared to remember it very well. Later, the memory was reactivated by a single morphine re-experience in the same context, and reconsolidation was disrupted by pharmacological treatments that were given either systemically or into the hippocampus, a brain region known to be important for the formation of memory of places. Taubenfeld et al. found that the memory of the place associated with the drug effects was indeed disrupted by the treatments. In addition, this disruption of the place-preference memory eliminated withdrawal, but only when that withdrawal was induced in the same place. Memory disruption only eliminated motivational withdrawal, whereas the physical signs of withdrawal were unaffected. Taubenfeld et al. suggest that disrupting drug-induced memories may provide a method for mitigating context-specific withdrawal and thereby preventing relapse in drug addicts.

Cristina Alberini is Associate Professor of Neuroscience, Psychiatry, and Structural and Chemical Biology at the Mount Sinai School of Medicine. Her current research interest is in learning and memory. Alberini has served as a panelist in the Philoctetes roundtables, The Biology of Freedom, The Psycho-Neurology of the Photographic Arts, and Addiction, and will participate in the upcoming roundtable, Psychoanalysis and Neuroscience: Ten Years Later.