Alcohol Addiction: Study Finds Brain Mechanism Which Explains Why Alcoholism Is Difficult To Beat

For the experiment, a number of rats were given regular small doses of alcohol, if they were willing to ensure a short, yet painful pulse of shock. These rats were trained to take as much alcohol as they wished, after which they were introduced to a healthier alternative with higher value- sweetened water. A small lever was used to supply the rats with this sugary water and this time, without any shocks. A significant number of rats chose to abandon the alcohol in favour of the shock-free sugar water. However, some 15 per cent of the rats still chose to continue consuming alcohol, despite the shocks.

The researchers said that there was a similar proportion of alcohol addicts, who prefer to continue with their alcohol habit, despite knowing the consequences full well. "'Only' about 10 to 15% of people exposed to alcohol develop alcohol-related problems. The behavioral repertoire of people confronted with opportunities to consume alcohol involves numerous choices between this drug reward and healthy alternatives", said the study. But why did the rats opt for the less healthy of the two alternatives, despite obvious deterrents? The answer, the researchers said, lies in the amygdala- a part of the brain linked to our emotional responses.

Through these experiments, scientists zeroed in on molecular rearrangements in the brain, which lead to impulsive and often self-destructive behaviours like addiction to alcohol. Researchers reached this conclusion by measuring how genes in five key areas' of the rats brains, got expressed in individual rats. The result proved that the amygdala of normal and addicted rats were very different. In the brains of addicted rats, there was found one particular gene, which was expressed at significantly lower levels.