Posted: Feb 08, 2012 3:03 am
by Mr.Samsa
Article wrote:"It's not like they're getting jackpot of sweets," says Dr Stoinski, who explains that the orangutans are content to interact with the screen even when the dispenser runs out of pellets.

"For some of them it is inherently rewarding," she tells BBC Nature.


Hmm.. unjustified assumption there. It seems more likely that, at least in the way its described above, the task is rewarding because it was rewarded in the past. The positive associations of an activity don't cease the moment the rewards stop coming..