“The experiment is simple. Put a rat in a cage, alone, with two water bottles. One is just water. The other is water laced with heroin or cocaine. Almost every time you run this experiment, the rat will become obsessed with the drugged water, and keep coming back for more and more, until it kills itself.
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But in the 1970s, a professor of Psychology in Vancouver called Bruce Alexander noticed something odd about this experiment. The rat is put in the cage all alone. It has nothing to do but take the drugs. What would happen, he wondered, if we tried this differently? So Professor Alexander built Rat Park. It is a lush cage where the rats would have colored balls and the best rat-food and tunnels to scamper down and plenty of friends: everything a rat about town could want. What, Alexander wanted to know, will happen then?
In Rat Park, all the rats obviously tried both water bottles, because they didn’t know what was in them. But what happened next was startling.
The rats with good lives didn’t like the drugged water. They mostly shunned it, consuming less than a quarter of the drugs the isolated rats used. None of them died. While all the rats who were alone and unhappy became heavy users, none of the rats who had a happy environment did.
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After the first phase of Rat Park, Professor Alexander then took this test further. He reran the early experiments, where the rats were left alone, and became compulsive users of the drug. He let them use for fifty-seven days — if anything can hook you, it’s that. Then he took them out of isolation, and placed them in Rat Park. He wanted to know, if you fall into that state of addiction, is your brain hijacked, so you can’t recover? Do the drugs take you over? What happened is — again — striking. The rats seemed to have a few twitches of withdrawal, but they soon stopped their heavy use, and went back to having a normal life. The good cage saved them.”