A study published this week by a Team at University College London suggests that Ketamine may prevent the brain retrieving memories that trigger relapses.

Maladaptive Reward Memories (MRM) are abnormally strong memories that are formed during rewarding but potentially harmful behaviours, such as drinking, taking drugs, or binge eating. These memories are often retrieved by a person’s brain when stimuli associated that memory are encountered, such as the smell of beer. Previous research has established that these stimuli, also known as trigger cues, and retrieving the MRM will cause consistent relapses.

Ketamine is a drug that has seen increased research into its psycho-pharmacologic uses in recent years, such as using it as an antidepressant. One of its many effects includes interfering with memory retrieval and memory reformation, and so it has been suggested that it may be useful for combatting MRM.

The team at UCL took a group of 90 participants who had no diagnosis of alcoholism or alcohol abuse disorder, but did admit to drinking an excessive amount of beer. The participants were asked to rate their interest in a selection of images of beer, soft drinks, orange juice and wine as well as their desire to drink beer, before being given a serving of beer. Once the participants drank this, they were asked about their desire to drink more beer.

A few days later, the participants returned and were split into three different groups – the first two groups were shown images of beer and orange juice respectively, before being given intravenous ketamine. The third group was shown images of beer, but received a placebo saline solution injection. In both group one and three, the images of beer were used as a trigger cue for MRM retrieval.

The final step was to regather the participants a week later, and ask their desire to drink beer – all three groups showed a significant decrease in their desire, but the first group who were reminded of beer before being given ketamine showed the biggest decrease in desire.

It is worth bearing in mind that this is a small study performed more to demonstrate future paths for further research, and that it doesn’t speak to the long term safety of taking ketamine, a drug with a lot of potential hazards. Despite these concerns, this research gives a useful understanding of the potential use of mind altering drugs in treating debilitating mental conditions.