Comparative behavior of primates. I. Delayed reaction tests on primates from the lemur to the orang-outan.
Publication Type: |
Journal Article |
Year of Publication: |
1932 |
Authors: |
Harlow, H. F.; Uehling, H.; Maslow, A. H. |
Publication/Journal: |
Journal of Comparative Psychology |
Keywords: |
anthropoid apes, delayed-reaction ability, delays, direct and indirect method, increased ability., lemur, new world monkey, old-world monkey, orang-utan, white-handed gibbon |
Abstract:
Using both the direct and indirect method, the authors tested the delayed-reaction ability of 2 anthropoid apes (an orang-utan and a white-handed gibbon), 19 old-world monkeys, 2 new-world monkeys, and 1 lemur. The animals were tested in their cages in the zoo. Delays of 0, 5, 15, 30, 60, 120, 180, and over 180 seconds were used. The results show an increased ability progressing from the lemur and South American monkeys to the anthropoid apes. It is pointed out that this ability parallels Tilney’s neurological classification. The ability to use representative factors was evident in every instance, but it varied in degree. Marked individual differences, as well as differences between genera, were evident. “There is evidence to indicate that, if the difficulty of the problem is such that the animal is unable to solve it immediately (insight), the primate characteristically attempts the solution in some simple and inadequate manner, gradually eliminates these methods, and finally solves the problem. If the difficulty of the problem is then increased, the animal tends to revert to the same inadequate types of response.” High test-retest correlations were found. Extraneous sensory cues were controlled without affecting the accuracy of response.