It seems intuitive that we want things because we like them, and that this simple relationship guides behavior; wanting provides the motivation to seek out the thing that gives us pleasure. For instance, I want pizza because I like pizza, and so I'll go get a slice for lunch.
However, in a recent paper published in the Journal of Experimental Psychology: Animal Learning and Cognition, Anselme and Robinson (2016) (PDF, 159KB)opens in new window review the evidence suggesting that "wanting" — the motivational attractiveness of a stimulus — and "liking" — the pleasure derived from a stimulus — are dissociable. Moreover, "wanting" and "liking" can be distinct from explicit conscious experiences of wanting and liking. This has important implications for understanding the maladaptive and often self-destructive behavior seen in human addiction.
The dissociation between "wanting" and "liking" can be puzzling: why would someone want a reward if they do not like it? Nevertheless, highly addictive drugs produce strong cravings despite little or diminishing feelings of pleasure.
Because dopamine guides reward salience, not the hedonic impact of the reward when it actually arrives, changes in dopamine neurons and the mesolimbic dopamine system following prolonged drug use increase "wanting" responses to drugs and drug-related cues because the reward is made more salient, while the pleasure derived from taking those drugs is unaffected. This increase in "wanting" makes drug addiction difficult to overcome even when addicts are highly motivated and are explicitly trying to do so, and makes relapse likely even months or years after recovery.
These issues are exacerbated by the fact that the influence of "wanting" on behavior is not under conscious control, and does not require a subjective feeling of craving. For example, recovering addicts who could freely choose between a low-dose cocaine or saline injection systematically chose the cocaine option, despite no difference in subjective feelings or cardiovascular responses to the two injections, and despite the fact that they thought they were choosing both options equally.
Thus, behavior can be guided by unconscious motivation to acquire rewards, regardless of the pleasure experienced when the reward is ultimately attained. Within this framework, drug addiction is easier to understand than other addictive behaviors, like gambling, because a drug should theoretically deliver a reward every time it is taken, whereas rewards in gambling are by definition unreliable.
So why does a problem gambler continue to play the slot machine despite a long string of failures that do not produce rewards? Anselme and Robinson suggest that reward uncertainty actually increases "wanting" because obtaining a reward when there is a possibility of missing it makes the reward more attractive, thereby increasing its salience.
This makes sense under certain circumstances. For instance, animals need to maintain sufficient motivation to seek resources necessary for survival when the rate of failure is high and environmental cues are not perfectly predictive of success. Unfortunately, this same process leads to an increase in dopamine in response to losses in problem gamblers, triggering a greater urge to play despite the negative financial consequences.
In other words, gamblers do not enjoy losses, but they find losses motivating.
Citation:
- Anselme, P., & Robinson, M. J. F. (2016). "Wanting," "liking," and their relation to consciousness. Journal of Experimental Psychology: Animal Learning and Cognition, 42(2), 123–140. https://dx.doi.org/10.1037/xan0000090
Note: This article is in the Basic / Experimental Psychology topic area. View more articles in the Basic / Experimental Psychology topic area.