THE BEHAVIORAL ECONOMICS OF CONCURRENT DRUG REINFORCERS - A REVIEW AND REANALYSIS OF DRUG SELF-ADMINISTRATION RESEARCH

In economics, goods can function as substitutes, complements, or be in dependent of one another. These concepts refer to increases, decreases , or no change in the consumption of one item as the price of a second item increases. This review examined whether these economic terms can be used to describe relationships between concurrently available rein forcers in drug self-administration research. Sixteen drug self-admini stration studies that examined the effects of concurrent reinforcers w ere identified through a MEDLINE search. Across these studies, the fol lowing substances were employed: caffeinated coffee, cocaine, etonitaz ene, ethanol, heroin, food, methadone, morphine, nicotine cigarettes, pentobarbital, phencyclidine, sucrose and water. These studies were re analyzed and the results were shown to be consistent with these econom ic notions. These analyses also showed that relationships among the co ncurrently available reinforcers were reliable within and across studi es, that concurrently available reinforcers can affect each other asym metrically, and that the relative price may determine the magnitude of effect for substitutes. These findings suggest that these economic co ncepts may be useful in characterizing the type and magnitude of inter actions between concurrently available reinforcers and may suggest pot ential mechanisms that determine these relationships.