Another group lived in what the researchers call an enriched environment up to 20 mice per cage,with toys, hiding places,and running wheels.

VOA: standard.2010.07.14

The experiment was, he would put--the pigeon was in a cage and he'd let the pigeon get pretty hungry -hungry pigeons are not happy pigeons.

实验过程是,他把鸽子困在笼子里,还不给鸽子喂食,饥饿的鸽子怒火中烧

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I don't think they were having very good success, but they did notice something interesting which is that the rat kept returning to the corner of the cage in which it was stimulated the day before So Olds got an interesting idea, he said, what if we let the rats stimulate in its own brain, what would happen.

他们的试验并不是非常成功，但他们确实是注意到了一些有趣的事情,老鼠总是会回到,昨天接受刺激的那个箱子的角落,因此奥兹产生了一个有趣的想法，他想，如果我们让老鼠在自己的脑中对自己进行刺激会，发生什么事情。

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