RESOLVING THE CONTRADICTIONS OF ADDICTION

Research findings on addition are contradictory. According to biograph ical records and widely used diagnostic manuals, addicts use drugs com pulsively, meaning that drug use is out of control and independent of its aversive consequences. This account is supported by studies that s how significant heritabilities for alcoholism and other addictions and by laboratory experiments in which repeated administration of addicti ve drugs caused changes in neural substrates associated with reward. E pidemiological and experimental data, however, show that the consequen ces of drug consumption can significantly modify drug intake in addict s. The disease model can account for the compulsive features of addict ion, but not occasions in which price and punishment reduced drug cons umption in addicts. Conversely, learning models of addiction can accou nt for the influence of price and punishment, but not compulsive drug taking. The occasion for this target article is that recent developmen ts in behavioral choice theory resolve the apparent contradictions in the addiction literature. The basic argument includes the following fo ur statements: First, repeated consumption of an addictive drug decrea ses its future value and the future value of competing activities. Sec ond, the frequency of an activity is a function of its relative (not a bsolute) value. This implies that an activity that reduces the values of competing behaviors can increase in frequency even if its own value also declines. Third, a recent experiment (Heyman & Tanz 1995) shows that the effective reinforcement contingencies are relative to a frame of reference, and this frame of reference can change so as to favor o ptimal or suboptimal choice. Fourth, if the frame of reference is loca l, reinforcement contingencies will favor excessive drug use, but if t he frame of reference is global, the reinforcement contingencies will favor controlled drug use. The transition from a global to a local fra me of reference explains relapse and other compulsive features of addi tion.