Ed Yong in The Atlantic:
“We cured alcoholism in every rat we ever tried,” says Heilig, who is now at Linköping University in Sweden. “And at the end of every paper, we wrote: This will lead to an exciting treatment. But everything we took from these animal models to the clinic failed. We needed to go back to the drawing board.”
Heilig doesn’t buy that mice and rats have nothing to teach us about addiction. It’s more that researchers have been studying them in the wrong way. Typically, they’ll let the animals self-administer drugs by pressing a lever, which they almost always learn to do. That should have been a red flag. When humans regularly drink alcohol, only 15 percent or so become dependent on the stuff. Why them and not the other 85 percent? That’s the crucial question, and you won’t answer it with an experiment in which every rodent becomes addicted.