Boren, J. J. (1966).
An experimental social relation between two monkeys.
Journal of the Experimental Analysis of Behavior,
9, 691-700.
A technique was developed for studying the reinforcement of one
organism by another. Two pairs of monkeys served as subjects in
adjoining but separate lever-pressing chambers. However, they
were in visual, aural, and tactile contact with each other. After
both pairs were trained to tolerate delays of reinforcement and
one pair was trained under stimulus control to exchange
reinforcements, monkey A of each pair pressed a lever to feed
monkey B, and monkey B pressed to feed monkey A. The experiment
sought to determine if this social interaction could be
maintained. With a free responding procedure where the monkeys
could work at any time in any order, the social relation proved
unstable. After several oscillations in which one monkey did most
of the responding and the other monkey did most of the eating,
the reinforcement frequency for both pairs of animals decreased
to very low levels. The final outcome would have been starvation
had the experimenter not intervened.