Teaching sign language to a chimpanzee, Gardner and Gardner (1969)

Aim: To see if a chimpanzee can be taught to use American Sign Language

Design: Longitudinal Case Study

Materials: A mobile home (where the Chimpanzee lived) Toys

Procedure: Washoe, a chimpanzee, was looked after in a mobile home and had a similar routine to a child. Life evolved around feeding and playing. She was trained to use American Sign Language using Operant Conditioning. Washoe was encouraged to imitate signs and she was rewarded with a tickle for imitating a sign. A sign was recorded as learnt when 3 observers saw the sign used in the correct context over 15 consecutive days

Results: Washoe learnt 30 signs after 22 months. She was able to display some of the following key features of language: differentiation, transference and combining signs. This study supports the view that language is learnt through positive reinforcement.