Behavioral economics and drug choice : effects of unit price on cocaine self-administration by monkeys

FRANÇAIS :
L'application des théories microéconomiques à l'étude expérimentale du comportement a été désignée par les termes "économie du comportement". L'article reprend ici les résultats d'études de renforcement de la consommation de cocaïne chez des singes, en comparant différents modèles mathématiques. Il semble que les changements de dose, ou de conditions requises pour obtenir une réponse n'ont pas nécessairement le même effet fonctionnel sur la consommation de drogues par les singes.
ENGLISH :
The application of microeconomic theory to the experimental analysis of behavior has been termed behavioral economics. There has been an increasing interest in applying the concepts of behavioral economics to the study of drug self-administration. In a previously published experiment (Nader and Woolverton, 1992), rhesus monkeys (N=3) were trained in a discrete-trials choice procedure and allowed to choose between intravenous injections of cocaine (0.03-1.0 mg/injection) and food presentation (1 or 4 pellets ; 1 g/pellet) during daily 7-h experimental sessions. When cocaine or food was available under a fixed-ratio (FR) 30 schedule, cocaine intake increased in a doserelated manner for all monkeys. When the response requirement (FR) for cocaine was differentially increased by doubling or quadrupling, the frequency of cocaine choice decreased, shifting the cocaine doseresponse function to the right. The present paper is a reanalysis of data from that experiment. Several mathematical models, differentially incorporating the effects of FR, dose and number of food pellets, compared. These results suggest that changes in FR and dose do not necessarily have the same functional effect on drug consumption and that the applicability of the UP model to drug selfadministration may be limited.