Human drug taking under controlled laboratory conditions.

The data presented point to the importance of studying drug effects under the conditions in which those drugs are taken outside of the laboratory. Interactions between the reinforcing and other direct effects of these drugs, as well as their interactions with ongoing environmental events, can only be evaluated under such conditions. Tolerance to cocaine's effects which can lead to a potential for increased toxicity, the regularity of both cocaine and marijuana self-administration under both stable and varying environmental conditions, and the regulation of caloric content of food all are important factors in understanding (and therefore being able to manipulate) substance use and abuse. These data also support the utility of a residential research facility for the investigation of substance use under conditions that approximate those in which people live outside of the laboratory. This unique laboratory, designed for continuous observation of human behavior over extended periods of time, provides a carefully controlled research environment with flexibility for establishing a range of subject behaviors and recording both individual and social behavior patterns. We can study regulation both within a day and over days, assessing the effects of experimental manipulations on the patterning of self-administration behavior. The design of such studies is a logical extension of those reported in the animal laboratory as well as those carried out in a more traditional human behavioral pharmacology laboratory.