A recent study on cocaine addiction in rats sheds new light on the risk of developing a compulsive behavior — 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 behavior. This could lead to future improved treatments of drug addictions instead of the current substitution therapies.

A lack of dopamine receptors in a specific brain region could trigger increased compulsions, such as drug addiction.

Source: Scientific American