Morphine addiction in chimpanzees (1940)

Spragg, S. D. S.

Abstract

Author provides formal description of training four unrestrained chimpanzees to approach an investigator and accept an injection of physiological saline solution. The training comprised a combination of adaptation, desensitization, and shaping, with fruit, praise, and patting as reinforcers. It is the writer's contention that this preliminary adaptation to the injection situation was an important factor for the experiment; it obviated many undesirable aspects which would have appeared if it had been necessary to inject the animals by force.