Visalberghi, Elisabetta; Limongelli, Luca
Journal of Comparative Psychology, Vol 108(1), Mar 1994, 15-22.
Four tufted capuchin monkeys, successful in a tool task in which they used a stick to push a reward out of a tube, were tested in a similar task, with a tube with a hole and a small trap. Depending on where the stick was inserted, the reward was pushed either out of the tube or into the trap. With the trap-tube task, the authors assessed whether the monkeys understood the cause–effect relation between their behavior and the outcome. In Exp 1, each S underwent 14 10-trial blocks with the trap tube. Three Ss performed at chance level. The 4th S's (Rb) performance improved, reaching 95% success in the last 6 blocks. In Exp 2, Rb received additional tests to investigate its successful strategy further. Rb solved the trap-tube task by means of a distance-based, associative rule. The performances of the 4 Ss indicate that they did not take into account the effects of their actions on the reward. (PsycINFO Database Record (c) 2012 APA, all rights reserved)