Scientists have left the rats sober by removing cocaine memories

Rats Drug

Once drug addiction is in place, staying clean can be as difficult as it may be: at least 70% of cocaine users relapse within 90 days.

Researchers at the University of Pittsburgh think they have found a way to prevent relapse that looks like a conspiracy in "Sunny Shadow of the Spotless Mind". By erasing memories related to cocaine use, they alleviated drug-seeking behavior in rats. – and they believe that the same therapy could help humans overcome their addiction to drugs.

Exhibition therapy

In a study published Tuesday in the newspaper Cell reports, the researchers describe how they hooked cocaine to rats by giving them a dose when they pressed a lever that also triggered a tone and a light. Eventually, the rats started pressing the lever each time they heard the tone and saw the light – a sign that the stimuli triggered the rats' desire for the drug.

Then, to break the link between the triggers and the drug-seeking behavior, the researchers changed the configuration so that when the rats pressed the lever to hear the tone and see the light, they had no cocaine. After a while, the rats stopped pushing to press the lever despite the presence of the triggers, a sign that the therapy actually stopped the drug-seeking behavior.

However, when they were moved to a different environment, the animals again began to press the lever in response to tone and light.

Deleted memories

By studying the brain of rats, researchers were able to identify the connections between two parties – the medial geniculate nucleus and the lateral amygdala – as playing a key role in forming memories that led animals to badociate tone with light. cocaine.

They then used a light-based technique, called optogenetics, to control neurons located between the two parts of the brain, effectively erasing memories of cocaine use in some rats. Indeed, these rats pressed the lever a lot less times when they were exposed to tone and light – and the decreased desire for cocaine persisted even when scientists placed the rats in a new environment.

"It made sense to us because it is in the amygdala that emotional memories form," said researcher Matthew Rich in a press release. "He receives a sensory input and badociates this input with what we feel when the signals are presented to us."

The researchers believe that their study on erasing memories badociated with drug use could help humans stay clean.

"In the long-term, these findings could help us develop drugs or approaches such as deep brain stimulation to specifically target these memories enhanced by psychoactive substance use and improve the success of exposure therapy to prevent relapses, "said researcher Mary Torregrossa.

READ MORE: Clear cocaine memories could help prevent relapses [UPMC]

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