Not found!? Well, I'm just the motile conglomeration of vermin for the job! "Rat Park", a utopia for rats, is (IMO) a critical component of the pushback against the disease model of addiction. An illustrated summary can be found in this lovely comic [0], while more interested parties can peruse the works of Dr Bruce Alexander, in the form of a blog-retrospective [1], or a slightly more technical presentation to the Canadian Senate [2], or his excellent book, The Globalization of Addiction: A Study of Poverty of the Spirit [3].
A layman-readable synthesis goes something like this: folk wisdom holds that some drugs are insanely addictive, as an inherent property of the drug. But this has generally [4] been borne out by introspective interviews of inveterate drug abusers and highly technical experimentation on lab animals (mostly social animals, like primates and rats). Introspection, for most domains of psychological study, is never used and treated as hearsay (it's not a contentious claim in psychology that people aren't good at examining their own mental states in a scientifically useful way). The methods of the experiments on social animals like rats and primates often dictate cramped, isolated and impoverished conditions. The "Rat Park" study took normal lab rats and placed them in an enormous array filled with nesting-boxes, large open areas, wheels and toys. The control rats, by contrast, were treated in every way identically to a standard addiction study -- tiny cage, no comforts, no stimulation but for a human changing their litter tray. Various experiments ensued, but even with different experimental treatments, the researchers couldn't induce addiction in the rats of Rat Park, while even fiercely bitter, heavily-diluted morphine-water was the choice of the isolated, imprisoned rat.
The orthodoxy of invincible permanent addiction was vanquished in these animals (and the minds of the researchers), by providing a more stimulating, spatious environment filled with fellow rats with whom to interact. This might say something important about the nature of addiction in other social animals, like humans.
[0] http://www.stuartmcmillen.com/comics_en/rat-park/
[1] http://www.brucekalexander.com/articles-speeches/rat-park/14...
[2] http://www.parl.gc.ca/content/sen/committee/371/ille/present...
[3] https://scholar.google.com/scholar?q=The+Globalisation+of+Ad...
[4] It IS true that you can see pretty drastic rewiring in the ventral tegmental area (which covers, generally, reward systems, drug addiction, strong emotions) with things like nicotine and cocaine, so the picture is probably more complicated than 'it's purely a social problem', but the ascendancy of the dogma of the disease model of addiction functionally prevents further study. Note that the Rat Park paper was very difficult to publish and received no attention for years.