A new research has found a mechanism in the brain that could be the reason behind addiction of alcohol over a healthier alternative. Researchers from the Linköping University, Sweden used rats to study this phenomenon. In the experiment, a number of rats were given a small dose of alcohol if they were willing to endure a short, but painful pulse of shock. Once they were trained to take as much alcohol as they wanted, they were then given an alternative.
Apparently, as per researchers, a small lever, when pulled would give the rats’ sweetened water, but this time without any shocks. Almost all the rats moved away from alcohol to enjoy the free, sweet water. However, about 15 percent of the rats were found to prefer the alcohol, even if it meant enduring the shocks. Among humans, there is a similar proportion of alcohol addicts.
The behaviour of the rats that preferred alcohol, notes the release, was found to be quite similar to addiction in humans, like the propensity to continue consuming the addictive substance in spite of negative consequences.
Researchers went on to investigate the reason why rats get addicted and to understand the exact mechanism behind this addiction. Scientists measured the expression of hundreds of genes in five key areas of the rats' brain. The largest differences between an addicted brain and a normal brain were found in the region of the brain called the amygdala, notes the report. This is also the region in the brain that is linked with emotional responses.
Through this experiment, scientists were able to identify molecular rearrangements in the brain that led to impulsive and sometimes even self-destructive addiction.
In the brains of the addicted rats, one gene, in particular, is expressed at significantly lower levels, notes the report. The same gene was responsible for maintaining low levels of inhibitory signal substance around the nerve cells regulated by GAT-3, a protein that worked as a transporter.