Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Rat Park was a study into drug addiction conducted in the late 1970s (and published in 1980), by Canadian psychologist Bruce K. Alexander and his colleagues at Simon Fraser University in British Columbia, Canada. Alexander''s hypothesis was that drugs do not cause addiction, and that the apparent addiction to opiate drugs commonly observed in laboratory rats exposed to it is attributable to their living conditions, and not to any addictive property of the drug itself. He told the Canadian Senate in 2001 that prior experiments in which laboratory rats were kept isolated in cramped metal cages, tethered to a self-injection apparatus, show only that "severely distressed animals, like severely distressed people, will relieve their distress pharmacologically if they can."