Liking, wanting, and the incentive-sensitization theory of addiction

Abstract

Rewards are both "liked" and "wanted," and those 2 words seem almost interchangeable. However, the brain circuitry that mediates the psychological process of "wanting" a particular reward is dissociable from circuitry that mediates the degree to which it is "liked." Incentive salience or "wanting," a form of motivation, is generated by large and robust neural systems that include mesolimbic dopamine. By comparison, "liking," or the actual pleasurable impact of reward consumption, is mediated by smaller and fragile neural systems, and is not dependent on dopamine. The incentive-sensitization theory posits the essence of drug addiction to be excessive amplification specifically of psychological "wanting," especially triggered by cues, without necessarily an amplification of "liking." This is because of long-lasting changes in dopamine-related motivation systems of susceptible individuals, called "neural sensitization." A quarter-century after its proposal, evidence has continued to grow in support the incentive-sensitization theory. Further, its scope is now expanding to include diverse behavioral addictions and other psychopathologies. (PsycINFO Database Record

Figure 1

‘Liking’ and ‘wanting’ in brain and in addiction. ‘Wanting’ is mediated by a robust brain system including dopamine projections (left, dark gray), whereas ‘liking’ is mediated by a restricted brain system of small hedonic hotspots (white) (described in Berridge & Kringelbach, 2015). The incentive-sensitization theory of addiction (right) shows how ‘wanting’ may grow over time independently of ‘liking’ as an individual becomes an addict, due to sensitization of brain mesolimbic systems. (The figure was adapted by Shannon Cole and Daniel Castro from Robinson & Berridge, 1993).