Can Alcohol Dependence Be Reversed

Here's the problem with alcoholism – and many other addictions – according to neuroscientists: the more you drink, the more times you activate certain clusters of neurons that trigger a reward sensation in your brain. You are creating a dedicated pathway between this bad behavior – drinking alcohol – and feeling good.

Now, what would happen if we could short circuit that pathway?

The neurons in question only comprise about five percent of the neurons in the brain’s central amygdala. The trick, as worked out by researchers at The Scripps Research Institute (TSRI), was to identify the ones that were activated by alcohol. After a series of experiments with alcoholic rats, they were successful.

“We can completely reverse alcohol dependence by targeting a network of neurons,” said TSRI Assistant Professor Olivier George, who led the study.

When the rats were then injected with with a compound that specifically deactivated only the alcohol-linked neurons, the rats ceased their compulsive drinking.

TSRI Research Associate Giordano de Guglielmo, who was the study’s first author, was astounded. “We’ve never seen an effect that strong that has lasted for several weeks,” he said. “I wasn’t sure if I believed it.”

The scientists re-ran the experiments several times and in each instance the rats stopped drinking compulsively. As part of the tests, the researchers noted that the rats were still motivated to drink sugar water, which confirmed that the team was able to shut down the alcoholic neurons, specifically. Even better, the procedure seemed immune from the traditional symptoms of alcohol withdrawl; that is, none of the rats got “the shakes.”

“It’s like they forgot they were dependent,” George noted.

The study had the happy extra benefit of shedding some light on the discrepancies between addictive consumption and occasional binge drinking. The deactivation of the drinking circuit neuron cluster had a minimal effect on future drinking. The researchers theorize that, in the case of the binging rats, the brain’s path from alcohol to reward had not yet been established.

“It is very challenging to target such a small population of neurons in the brain, but this study helps to increase our knowledge of a part of the brain that is still a mystery,” said de Guglielmo.

The research was published in The Journal of Neuroscience.