The Joyless Addiction
Desire without pleasure
Posted Jan 28, 2015
Addicts often express that they continue to use drugs even when they no longer derive any pleasure. For example, some cigarette smokers express a deep hatred of smoking, but they continue to smoke regularly. Similar experiences are reported for alcohol and morphine. Yet, despite this, addicts report almost irrational craving for the drug. The pleasure gap leads to joyless addiction. This puzzling aspect of addiction is best explained by the “incentive salience” theory of addiction. The theory is able to explain the dissociation between drug liking and drug wanting.
Desire is rational as long as people choose what they expect to like. Usually liking and wanting for pleasant rewards do go together, virtually as two sides of the same coin. Liking and wanting are linked over time by the learning system. For example, when the consumption of a highly liked food causes an allergic reaction, people learn to avoid that food item. In normal brain, wanting, liking, and learning processes are balanced. Achieving the right balance may be a key to happiness. For example, balanced wanting and liking can facilitate life enjoyment and engagement with the world.
A breakdown of the balance between liking and wanting can lead to bad decisions (or choices that are not liked). We see this in more ordinary desires such as buying exercise equipment, joining health club, compulsive shopping, and even the desire to pursue a certain career where there is a possible disconnection between the desire for these choices and the experienced pleasure from using them. The motives for the behaviors are distinct from the reflective judgments about what is valuable or even pleasurable. So a person who is motivated solely by desires will pursue mostly immediately rewarding goals without necessarily enjoying them.
The neuroscience literature pioneered by Berridge and colleagues draws a distinction between the liking system responsible for the feeling of pleasure and pain, and the wanting system responsible for the motivation or incentive to seek pleasure and avoid pain. Liking refers to the pleasure that comes from actually enjoying the experience, and wanting represents desire or pleasure anticipation. The liking effects include feelings of pleasure and facial reactions during the pleasurable condition. For example, infants constantly lick their lip when given sweet-tasting foods, and bad-tasting food will lead them to shake their head, and frantically wipe their mouths. The wanting effects include the desire and urge to obtain the drug, such as the feeling of craving.
Irrational wanting without liking can occur in addiction, where addicts strongly want to take a drug without necessarily liking the drug. The incentive salience theory suggests that after long periods of drug use, wanting dominates motivation for drug use, and addicts no longer derive much pleasure from their drug of choice. Repeated drug use produces a sensitized brain system, which leads to increased wanting. This excessive urges makes drug addiction so compulsive and resistant to recovery.
Sensitization refers to an increase in responsiveness. The increasing irritation produced by exposure to a disliked roommate is a familiar example of sensitization. Sensitization is the opposite of tolerance. In fact, the liking system tends to display a form of tolerance. The result is a paradoxical state where addicts often report that they want the drug, which is beyond liking the drug. Although liking and wanting drugs are strongly linked at the initial stage of drug use, only wanting becomes sensitized as addiction develops. As a result, addicts actually become more sensitive to the drug and they have a bigger response to a smaller dose than they did at first.
Neural sensitization can last for years, which suggests that recovering from addiction may be a long and slow process. Sensitization is the reason why many clinicians require complete drug abstention as a condition of treatment for addicts. An attempt to take even a single drink involves the danger of triggering an intense craving for further consumption. Furthermore, wanting can also occur in the absence of any form of cognitive awareness. This would explain why addicts have so little insight into their apparent desire for drugs and their cues.
In sum, the wanting system not only creates a strong (and misleading) impulse to seek and use the substance, but also undermines the potential for cognitive control. Addicts genuinely want to stop; and yet still they feel the pull of the desire. This is why it is often unreasonable to blame addicts for giving in to temptation. An effective treatment requires unite the wanting and liking mechanisms. Cognitive and behavioral therapies, as well as mindfulness meditation may gradually reduce some effects of sensitization. Among the many psychological benefits of training in mindfulness meditation is an improvement in selective attention to control their attention and help them to better resist desires.