Applying Game Theory to Recovery from Addiction

The ability to exercise self-control and resist temptation is a key to maintaining a new behavior. We exert self-control when we resist the urge to consume alcohol or eat an extra slice of chocolate cake. However, the biggest self-control challenge is to maintain that discipline not just for days or weeks but for a long time. In many cases, the pull of the drug/behavior can shift in favor of use. In the face of temptation, the vulnerable person attaches higher value to temptation and abandons prior promises.

The conflict between current and future selves can be seen as a prisoner’s dilemma. Although this theory was originally developed with reference to individuals, it could equally be applied to the transient selves (a person being a collection of transient selves over time) (Parfit, 1984). In this view, each self is considered an independent rational decision maker. Each self is also transient: she will not be (entirely) the same person tomorrow as she is today. For example, the individual who in the morning prefers to avoid overeating might prefer indulgence in the evening.

In the Prisoner’s Dilemma, two partners in crime are arrested and interrogated in separate rooms. The authorities give each prisoner the same choice: Confess your shared guilt (in effect, snitch on your partner) or remain silent (and be loyal to your partner). For example, if one betrays and the other stays silent, the snitcher goes free, and the silent, loyal one spends ten years in jail. If both remain loyal, both get six months. If both betray the other, both get five years.

Each person has the temptation to cheat the other to gain lower punishment. When both players pursue their own self-interest, both do worse than they would have if somehow they could have jointly and credibly agreed to remain silent. In short, game theory suggests that decisions that are best for the individual can be terrible for the group. Collectively, it would be best for both to keep quiet.

Applied to the self-control problem, the choice that the immediate self would prefer is to indulge today (a cigarette today) and quit starting tomorrow. It is in the best interest of her present self to have a drink. However, the self tomorrow will face the same decision and, hence, will not quit.

So we have a prisoner’s dilemma with smoking equivalent to giving up to cooperate. Each self might prefer the outcome of being a nonsmoker (all cooperate) to the outcome of a smoker (all betray) and reduce the risk of cancer. However, the cost of not using is born entirely by the immediate self (sacrificing the pleasure of smoking a cigarette) whereas the benefits of being a nonsmoker are shared across transient selves at the end of the person’s life (Rachlin, 2014). So the incentive is to say yourself … "I will start tomorrow."

We can use the insights from the prisoner dilemma to suggest ways to resist changing motivation. That is, an individual has incentives to develop a self-enforcing cooperative arrangement with her future selves. For example, the reason that people recovering from alcoholism avoid taking a single drink is to maintain the credibility of their sobriety. When you make an agreement and you don’t keep it, you undermine your own self-trust. Knowing that you were able to overcome the desire to drink last night might make you more confident that you will be able to overcome the desire in the future, and thus more likely to resist tonight.

Thus, it is not a good idea to make many sorts of decisions on a case-by-case basis. On a case-by-case basis, most of us would be having that second dessert or drinking that third martini at a party. There is considerable evidence that when behavior is organized into coherent patterns, self-control increases. For example, the decision to stop smoking is in effect a decision to begin a pattern of behavior. Not smoking tonight makes it easier not to smoke tomorrow and not smoking tomorrow makes it easier not to smoke the next day, and so on. By tying together sequences of choices, the individual aligns his short-term incentives with his long-run interests. In doing so, the person behaves so as to maximize the rewards of the present and distant selves.

In general, self-control problems are partly associated with a lack of identification with the self over time. Recovery from addiction requires a measure of integration between his different selves, and between his past and his present. The motivation to sacrifice consumption on behalf of future selves depends on how “connected” the current self feels toward those future selves with respect to personal identity, such as beliefs, values, and goals. Research shows that having psychological connection with our future selves as sharing memories, intentions, beliefs, and desires increase patience (Bartlels & Urminsky, 2011). Thus, interventions that involve imagining one’s future self (e.g., viewing one’s aged self) may encourage people’s sense of connectedness with their future self.