Communication Skills and Disorders

WASHOE THE CHIMPANZEE

One of the most important case histories to the study of comparative psychology and language acquisition is that of a chimpanzee named Washoe. Born in West Africa, Washoe was adopted in 1966 by R. Allen Gardner and Beatrice T. Gardner at the University of Nevada. The Gardners set out to teach her American Sign Language (ASL) for a study they referred to as Project Washoe. This marked the first attempt to teach a chimpanzee to sign, although there had been several unsuccessful experiments attempting to teach chimps human speech.

Washoe was about 11 months old when the project began and 5 years old at the end of the training. Subsequent chimpanzee subjects used by the Gardners in similar studies participated from birth. Within 51 months of training, Washoe had acquired use of 132 signs and was additionally able to understand hundreds more.

Some scientists remain skeptical of the claims of language apprehension of Washoe and other primates, saying that the animals are merely acting on prompts from researchers, rather than engaging in true human-like conversation. However, the Gardners reported frequent spontaneous use of ASL by Washoe in her interactions with both humans and animals. They also reported that her signs were not merely replies, but that she also initiated communication with questions and opening statements.

The researchers attempted to replicate the sort of environment and conditions that a developing human child would experience, rather than keeping the chimp in a caged, laboratory setting. They believed that the development of language does notoccur in avacuum, but is influenced byotherfacetsof the behavioral environment and development. They described the chimps’ daily routine as follows: “Their waking hours follow a schedule of meals, naps, baths, play, and schooling, much like that of a young child; their living quarters are well stocked with furniture, tools, and toys of all kinds, and there are frequent excursions to other interesting places—a pond or a meadow, the home of a human or chimpanzee friend.”

The age at which chimpanzees in the studies produced their first words was earlier than the age at which hearing human children speak, but comparable to the age at which deaf children first begin to sign. Deaf children who are exposed to sign from birth have been reported as beginning to use it between the ages of 5 and 6 months.

The type of early signing the chimps engaged in was compared to human “baby talk,” similar in content to early speech of human children. The category of words known as “general nominals” (e.g. bib, flower, toothbrush) was shown to be most common in both human children and chimpanzees. The sign for “up” appeared very early in both humans and chimps, often in the form of a request to be picked up.

While it was notable for its significance to the study of comparative psychology, the Washoe study also is used in arguments for the ethical treatment of research animals. Many researchers and ethicists have argued that Washoe's behavior and learning capacity as well as her relationships with researchers proved that chimpanzees are emotionally sensitive and deserving of ethical treatment.

Washoe died in 2007 at the age of 42, but some of her family members survive. The non-profit organization Friends of Washoe was established in 1981 with the goal of ensuring the welfare of chimpanzees, particularly the surviving members of Washoe's family.

The Washoe study was instrumental in comparing language acquisition in children and chimpanzees. Chimpanzees closest relative to humans, sharing 98% DNA and the Gardners demonstrated the overlap of intellectual abilities between humans and chimpanzees.