Dopamine in disturbances of food and drug motivated behavior: a case of homology?

Highly palatable food and drugs of abuse share the ability to stimulate dopamine transmission in the shell of the nucleus accumbens. However, while in the case of food this property is adaptively regulated in a negative fashion upon repeated exposure to the reward, no such regulation is operative towards drugs of abuse. Dysadaptive stimulation of dopamine transmission in the accumbens shell is assigned an important role in the compulsive motivation for drugs typical of drug addiction. It is speculated that disturbances of feeding behavior are related to loss of adaptive regulation of food-stimulated release of dopamine in the shell of the accumbens.