The Grooming Behavior of the Chimpanzee as a ReinforcerJohn L Falk made a basic study on the grooming behavior of the chimpanzee. He noticed that the behavior was characterized by the animal’s stroking of its hair, extending its lips, freeing embedded dirt on its skin and putting it on its mouth. Falk wanted to find out if grooming could be a reinforcer that would motivate the chimpanzee to learn discrimination.Falk, the experimenter (E), conducted an experiment using a 3 years, 10 months old male chimpanzee as a subject.
This was the independent variable. He built a square plexiglas with two patterns – a box and a cross – glued in its surface. The objective was for the chimpanzee to touch each pattern in the plexiglas.
After the ape touched the box pattern, E put his right arm inside the cage and groomed the animal for 30 seconds. E rotated the plexiglas, exposing the cross pattern to the animal; but it did not receive grooming from E after touching the cross pattern. The process was then reversed: the chimpanzee got grooming for the cross pattern and not in the box pattern. This procedure was repeated several times until 10 reinforcements were achieved. The animal gave a positive response by touching the pattern where it could get grooming and displayed negative response to the pattern where grooming was not presented. This discrimination behavior of the animal was the dependent variable.
The grooming pattern or the opportunity to groom, which was the controled condition in the study, was used to determine if grooming affected the ability of the primate to discriminate.The experimenter found out that at initial test, the chimpanzee committed a high rate of error. However, as the experiment progressed, the error significantly diminished.
The chimpanzee learned the discrimination due to the reward it received from the experimenter in the form of grooming. The opportunity to groom served as a reinforcer for the animal to perform the task at hand. The animal also exhibited tantrums when the experimenter refused to groom.Work Cited:Falk, John L. (1958). The Grooming Behavior of the Chimpanzee as a Reinforcer.
Journal of the Experimental Analysis of Behavior, 1.p. 83-85.