The role of the orbitofrontal cortex in reward related behavior in addiction and alcoholism in particular

Abstract

Addiction can be conceptualized as a learning disorder as addicts are unable to regulate behavior associated with drug reward. Reward related learning has traditionally been associated with dopamine transmission in subcortical structures. Recent findings indicate however that the orbitofrontal cortex (OFC) in particular is able to modulate dopamine levels in subcortical structures, regulating reward value as well as choice behavior by providing information on the value of stimuli. Therefore the OFC is thought to be dysfunctional in addiction as addicts overvalue reward despite long term negative consequences. This review discusses structural and functional abnormalities of the OFC in addiction and in alcoholism in particular, as problematic consumption of alcohol is much more common than is problematic consumption of other substances. Furthermore, in an attempt to elucidate potential causal relations, genetic contributions to (alcohol) addiction and its predisposing factors are discussed, as well as animal studies on addiction and the OFC.