Re: I'd say that experiment . . .
I'd say that experiment shows a potential for addiction, but primarily addiction in the case of lab rats.
Humans, on the other hand, have been known to actually think their way out of these kinds of dilemma -- otherwise there would be no drug problem today. A race of humans with the intelligence to concoct addictive, life-threatening -- eventually life-taking -- drugs, but unable to reason their way out of, or away from, said addiction, would likely become extinct, if not for the power of abstract reasoning -- the same power which allows us to concoct the life-threatening drugs of addiction in the first place.
I like to think I'm a little more complex than the average lab rat (NIMH, of course, excluded),
Dan (sorry about that, Nicodemus)