A recent study on cocaine addiction in rats sheds new light on the risk of developing a compulsive behaviour — drug abuse, gambling, shopping, etc. — in humans. The number of D2 dopamine receptors in a specific area of the brain was formerly thought to decrease due to cocaine intake, but the results of this experiment demonstrate that it is in fact the original lower number of those receptors that is likely to trigger an impulsive or compulsive behaviour. This could lead to future improved treatments of drug addictions instead of the current substitution therapies.
If we can devise a drug that safely increases the number of those D2 dopamine receptors, impulsive/compulsive behaviours could be more efficiently controlled. The existing treatments maintain the state of dependence and simply substitute for the 'real' drug that abusers illegally take. This new therapy would tackle the problem directly.