A HAPPY RAT?
Photo of a rat self-administering drops of morphine.
Video clip (WMV; 0.87Mb) of a opioid-dependent rat repeatedly self-administering morphine. Although there analogies between wireheading and cocaine addiction, the parallel with opioid addiction is more distant. An opioid-dependent rat (or monkey, etc) needs progressively greater doses of morphine to gain the same subjective reward: the optimal dosage eventually plateaus out at hundreds of times the starting dose. Unlike self-stimulating or cocaine-taking rats, the morphine-dependent rat will still take time off to eat. Thus the morphine-dependent rat (or monkey, etc) can survive indefinitely even if given unlimited access to the drug. Unlike non-human animals, wired humans do not typically compulsively self-stimulate unless they are clinically depressed. An alternative interpretation of this finding is that most captive non-human animals are depressed; their chronic depression confounds the results of innumerable laboratory experiments.