If you know someone who’s suffering from alcohol or drug addiction, a little amnesia might be just the thing to get them back on the wagon, researchers at Tel Aviv University have shown.
“One of the main causes of relapse in alcoholics are memories linking objects and places connected to alcohol consumption, such as shops, liquor bottles, and of course the smell and taste of alcohol,” said Dr. Segev Barak of Tel Aviv University, who is leading a team studying ways to prevent recidivism in addicts. By “disengaging” the memories associated with alcohol, Segev’s team found, it was possible to significantly cut the return rate for alcoholics.
In fact, said Segev, “70-80 percent of alcohol and drug addicts ‘fall’ and return to their old ways, even a year after a successful detox.” The reason for that, Segev’s team found in a study published Sunday in the journal Nature Neuroscience, was due to strong memories associated with alcohol. But a study on lab rats who got hooked on alcohol and were then put through detox, showed that one particular protein was responsible for the retention and revival of these memories. By inhibiting the activity of this protein, the scientists found they could disrupt the associated memories that pull alcoholics back off the wagon.
In the study, researchers gave rats a choice between water and 40 proof (20%) alcohol, which the rats drank in large quantities on a voluntary basis for two months. Then the researchers trained rats to press a lever to obtain alcohol. The rats were then put through a 10-day detox, with researchers tempting them with the smell and taste of alcohol in their food.
Observing the rats, Segev said that the team found what could be a key to preventing recidivism. “When we retrieve a memory, a window of opportunity is opened which allows memory to be manipulated for several hours. During that time, memories undergo updating and remaking, in a process called memory reconsolidation. We found that during this process there is a very strong activation of protein within the nerve cell called mTORC1, responsible for the creation of new proteins at the junction of nerve cells in the brain (synapses), which plays an important role in memory.”
The researchers scanned the entire brain and discovered that memories of alcohol consumption — often prompted by external stimuli — caused activation of this protein in specific regions of the frontal cortex, the area of the brain related to memory processing, as well as in the nucleus of the amygdala, which is responsible for emotional memories and involved in the emotional symptoms related to withdrawal. The connection between the protein and these areas of the brain was very strong and specific, Barak said, far more so than for other proteins. “We knew right away that we had discovered something critical.”
Since the protein was activated when memories of alcohol use were revived, it stood to reason that disrupting the protein could disrupt the effect of the memories as well. The team indeed did establish that targeted neutralization of the protein activation immediately after memory retrieval led to a deletion of the memory and a days-long prevention of seeking out alcohol, where previously the drive to drink would have been all-encompassing. The neutralization is done using FDA-approved drugs to prevent organ rejection in transplants.
mTORC1 seems to be related to just alcohol, Segev said. “We found that other memories not related to alcohol, such as memories associated with natural rewards such as sugar, were unaffected. The disruption generated a deletion of memories related to alcohol, and was very strong. These rats simply have not returned to look for alcohol,” Barak said.
The research was carried out at Tel Aviv University and the University of California-San Francisco and will continue, with a focus on obtaining a better understanding of the brain and the biological mechanisms that underlie memory processes that cause vulnerability to alcoholism — and perhaps drug use — in some individuals. In addition, Barak is working on a behavioral treatment based on the research, to find out the best ways to implement memory disruption to end alcohol and drug recidivism, without the need for pharmaceuticals to control the urge. “If we can develop an efficient treatment without the use of drugs,” Barak added, “it will be a real revolution.”