Natural Rationality | decision-making in the economy of nature


A dual account of addiction?

In a recent edition of The American Journal of Bioethics, Steven Hyman presents the recent findings on the neurobiology and addiction (a clear and complete review, by the way), especially cognitive neuroscience, and how these researches could shed light on addiction, its control and its cure. Against the 'disease model' of addiction, that consider addiction as completely out of control, and the folk psychological model of voluntary action, according to which we have a conscious control over most of our actions, he shows that a more complex picture should be put forth. Yes, addiction is partly out of control, as reward-seeking mechanisms are hijacked by drugs of abuse and cognitive control mechanisms are impaired, but in appropriate environmental settings, relatives or friends may act as 'external prefrontal cortex' and help the addicted indiviual. Hyman's model of addiction seems to endorse (although he does not mention it explicitly) a dual-mechanisms account of cognition (the idea that the cognition operates through 2 systems, one fast/intuitive/automatic/parrallel, the other slow/reflected/controlled/serial). His conclusion aptly summarizes his point:

Mechanisms that evolved to motivate survival behaviors, the pursuit of natural rewards, are usurped by the potent and abnormal dopamine signal produced by addictive drugs. The result is a brain in which drug cues powerfully activate drug seeking, and in which attempts to suppress drugseeking result in intense craving. This model does not, however, reduce addicted individuals to zombies who are permanently controlled by external cues. As overvalued as drugs become, as potent as the effects of drug cues on behavior, other goals are not extirpated. Perhaps in a drug-free context, perhaps with a good measure of initial coercion, perhaps with family, friends, and caregivers acting as external "prostheses" to strengthen and partially replace damaged frontal mechanisms of cognitive control, and often despite multiple relapses, addicts can cease drug use and regain a good measure of control over their drug taking. Our current models help explain why recovery is difficult and why relapses occur even long after detoxification and rehabilitation. The long experience of humanity with addiction does not counsel fatalism, but implacable efforts to overcome the behavioral effects of neural circuits hijacked by drugs. Finally, views based on cognitive neuroscience and studies of addiction pathogenesis suggest that some apparently voluntary behaviors may not be as freely planned and executed as they first appear. Such cognitive views have not yet penetrated folk psychology, and it is premature for these views to have any place in the courtroom (Morse 2004a; Greene and Cohen 2004). Nonetheless these cognitive views deserve a place in current ethical discussions of personal responsibility. For many reasons, it may be wise for societies to err on the side of holding addicted individuals responsible for their behavior and to act as if they are capable of exerting more control than perhaps they can; however, if the ideas expressed in this review are right, it should be with a view to rehabilitation of the addicted person and protection of society rather than moral opprobrium.

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