Dissociation between wanting and liking for coffee in heavy drinkers.

Abstract

There is an ongoing discussion about the addictive strength of caffeine. According to the incentive-sensitization theory, the development and the maintenance of drug addiction is the result of a selective sensitization of brain regions that are relevant for wanting without a corresponding increase in liking. Dissociations of wanting and liking have been observed with a wide range of drugs in animals. For human subjects, results are inconclusive, which is possibly due to invalid operationalizations of wanting and liking. The present study examined dissociations of wanting and liking for coffee in heavy and low/non-consumers with newly developed and validated response time-based assessment procedures for wanting and liking. For this study 24 heavy and 32 low/non-consumers of coffee completed two versions of the Implicit-Association Test (IAT), one of which has been developed and validated recently to assess wanting for coffee, whereas the other reflects an indicator of liking for coffee. Results revealed a significant interaction between group (heavy vs. low/non-consumers) and IAT type (wanting vs. liking) indicating that heavy coffee drinkers differed from low/non-consumers by displaying increased wanting but not liking for coffee. These data confirm that heavy coffee consumption is associated with strong wanting despite low liking for coffee, indicating that wanting becomes independent from liking through repeated consumption of caffeine. This dissociation provides a possible explanation for the widespread and stable consumption of caffeine-containing beverages.