Drugs for Therapeutic Forgetting? – Forget about it.

Over that past decade, there has been a great deal of interest in the prospect that we might be able to edit unpleasant memories (a phenomenon dubbed therapeutic forgetting) by capitalizing upon the phenomenon of reconsolidation.  The basic idea is this: although memories are stable for years, when we recall a memory it becomes labile.  Once the memory is transformed into this more flexible state, it can be modified by subsequent experience.  The memory is not lost, but becomes reconsolidated (most probably during the subsequent night’s sleep); in this way, new experiences are integrated with old ones, providing a mechanism by which experiences throughout the lifetime can be in amalgamated in meaningful fashion.

Spearheaded by studies from Joseph Le Doux’s laboratory, several groups have reasoned that if one were to induce individuals to recall problematic memories and then interfere with reconsolidation using pharmacological means, we might be able to specifically amend our memories of past events.  From a therapeutic perspective, this would be most useful in treating patients with post-traumatic stress disorder (PTSD) in which the memories of certain emotionally charged events become so troublesome that they have outsized effects on the quality of life.  The problem has been with the potential side effects of the pharmacological approach – protein synthesis inhibitors, partial NMDA receptor agonists, viral vectors with toxins as the payload, & beta-adrenergic receptor blockers have all been shown to be effective in laboratory experiments, but, with the notable exception of beta-blockers, none are really suitable for use in the clinical setting.

But a good idea does not lay fallow for long, and a collaboration between Elizabeth Phelps and Joe LeDoux’s groups has again advanced the field in impressive fashion. Continue reading