Implicit measures of “wanting” and “liking” in humans

IST makes the clear prediction that (1) there should be a positive correlation between indices of “wanting” (e.g., drug consumption) and implicit “wanting” scores. Similarly, there should be a positive correlation between indices of “liking” (e.g., various expressions of subjective pleasure) and implicit “liking” scores; (2) there should be higher “wanting” scores in substance abusers or frequent substance users compared to non-users or infrequent users, and there should be no differences in “liking” between these groups (or even less “liking” in frequent substance users); (3) manipulations of “wanting” should affect implicit “wanting” scores whereas manipulations of “liking” should affect implicit “liking” scores. However, studies that tested these hypotheses did not produce equivocal results. To shed light on these discrepancies, we first discuss the different definitions of “wanting” and “liking” and the different tests that have been used to assess these processes. Then, we discuss whether it is reasonable to assume that these tests are valid measures of “wanting” and “liking” and we review correlational, quasi-experimental, and experimental studies that inform us about this issue. Finally, we discuss the future potential of implicit measures in research on IST and make several recommendations to improve both theory and methodology.