Rat Park

Rat Park was a series of studies into drug addiction conducted in the late 1970s and published between 1978 and 1981 by Canadian psychologist Bruce K. Alexander and his colleagues at Simon Fraser University in British Columbia, Canada. At the time of the studies, research exploring the self-administration of morphine in animals often used small, solitary metal cages. Alexander hypothesized that these conditions may be responsible for exacerbating self-administration. To test this hypothesis, Alexander and his colleagues built Rat Park, a large housing colony 200 times the floor area of a standard laboratory cage. There were 16–20 rats of both sexes in residence, food, balls and wheels for play, and enough space for mating. The results of the experiment appeared to support his hypothesis that improved housing conditions reduce the consumption of morphine water. This research highlighted an important issue in the design of morphine self-administration studies of the time, namely the use of austere housing conditions, which confound the results.