WJEC Psychology PY2Core Studies

Gardner, B. T. & Gardner, R. A. (1969) “Teaching Sign Language

to a Chimpanzee”

Objectives

• To consider the skills involved in human language.

• To identify differences between animal communication and human language

• To describe the aims and context of Gardner and Gardner’s study

Starter activity http://lingclub.mycpanel.princeton.edu/challenge/agta.php

Explain what skills you needed to solve this puzzle.•Semantics (meaning) Understand English text.•This involves creating a representation of something using another symbol • becomes CLOUD

•Keep the meaning but alter the symbols (new language)•CLOUD becomes WOLKE (German)•Syntax Use rules to put the new words in the right order•Productivity use the new symbols (words) to create new meaning

Communication and Language

• Communication - transmitting information from one individual or group to another individual or group.

• Animals can certainly communicate with each other. The debate is about whether they can use something similar to human language to do this.

• Language is sounds, letters, gestures, that by themselves are meaningless, but which can be organised into meaningful combinations and using certain rules, make an infinite number of messages.

What is Language?

Charles Hockett (1960)

“Design Features of Language”

• Interchangeability

• Semanticity

• Displacement

• Productivity

• Learning and Transmission

• Explain why this study is from the cognitive approach.

Context• Read about Chomsky’s LAD – What is it? What

does it suggest about language acquisition?• If a chimp can be taught to use and understand

language, then humans are not unique in being able to communicate this way.

• Hayes and Hayes(1951) spent several YEARS teaching a chimp called Vick to say FOUR words.

• Premack and Premack (1966) raised a chimpanzee, Sarah, and taught her to use different coloured and shaped chips to represent words.

Context Continued

• Perhaps the problem is in chimps vocal cords – if we provide them with another way of “speaking” they could develop the use and understanding of language.

• http://www.youtube.com/watch?v=OUwOvF7TqgA

• http://www.youtube.com/watch?v=2Dhc2zePJFE&feature=related

• http://www.youtube.com/watch?v=wRM7vTrIIis&feature=relmfu

Aims

• Allen and Beatrice Gardner wanted to see if a chimp could communicate with humans.

• Chimps are constrained by their vocal chords from repeating some sounds, so the Gardners wanted to see if a chimp could learn sign language. http://www.youtube.com/watch?v=OUwOvF7TqgA

Objectives

• What processing is involved in human language?

• What are the differences between animal communication and human language?

• What design elements of language did you see Kanzi using?

• What was the context and aims of Gardner and Gardner’s study?

•

Method

• A single participant experiment (chimpanzee named Washoe)

Participant

• A chimpanzee named Washoe who was between 8 – 11 months old when first acquired by the Gardners.

• She had been born in the wild in Africa and taken to America.

• A chimp was chosen because they are intelligent and sociable.

Procedure

The researchers decided to teach Washoe American Sign Language (ASL) for several reasons:

• Chimps are physically unable to vocalise some sounds.

• Chimps are very good at using their hands.• ASL is equivalent to spoken language.• ASL would allow them to compare Washoe’s

progress with that of deaf children who also learn ASL.

Procedures

• All people who dealt with Washoe had to master ASL.

• The Gardners made sure that Washoe had lots of companions who were also learning ASL.

• All communication with Washoe was through ASL approved signs.

Procedures

• Operant conditioning training methods were used which meant that each time Washoe produced a sign that was recognisable, she was rewarded by being tickled (she loved being tickled).

• Shaping – at first rewarded for a similar sign, eventually only rewarded for an exact copy

• Records were kept of her signing behaviour.

Procedures

Training Methods

• Imitation – “Do this game”

• Prompting – correcting “sloppy” signs

• Using Signs – during all activities and games

Procedures

Training Methods

• Babbling – repeating and correcting Washoe’s babbling

• Direct Tuition – forming Washoe’s hands into new gestures.

Procedure

• To decide whether a sign had been learned properly a double blind procedure was used by the researchers.

• They put a box with a picture inside where Washoe would play.

• When she opened the box and saw the picture, she made a sign.

• The sign was observed by a researcher and noted.• A second researcher, who could not see the box, also

recorded what they thought the sign that Washoe had made represented.

• This was then checked and only if the sign corresponded to the picture and was used in context for a period of 15 consecutive days, was it counted as being learned.

Findings

• Washoe spontaneously imitated but it wasn’t until the 16th month of work (when Washoe was about 2 – 2½ years old) that the Gardners had any control over her gestures.

• They encouraged her to babble by smiling, clapping and repeating, especially when the babbling resembled ASL.

Findings

• Washoe learned the term ‘more’ through play.• At first she would indicate she wanted more tickling by

putting the researcher’s hands on her ribs. • They noticed that when she was tickled, she put her

arms together to cover the area being tickled.• This gesture is very similar to the ASL sign for ‘more’.• They encouraged her by rewarding her whenever she

used the sign by more tickling.• She soon learned to associate the sign with the tickling

that resulted.

Findings

• At the end of 21 months, Washoe could use about 30 word signs.

• 4 other words – dog, smell, me and clean- were stable but didn’t meet criteria.

• More – food/tickling• Drink – for water. Pop = drink+sweet• Sorry – After biting someone, when told to

apologise.• Baby – Dolls: human or animals• Please – asking for object or activity

Findings

• She could combine the signs to make short messages such as ‘Washoe go out’

• She was also able to invent novel phrases, such as when she saw a swan for the first time she signed ‘water bird’.

Findings

Washoe’s language resembled human children in 3 ways:

• Differentiating – Separating signs for different meanings eg “flower” “smell”

• Transfer – generalising from one flower to other types of flowers

• Combining Signs – putting together phrases eg “listen dog” “baby in my drink”

Conclusion

• The choice of sign language was a good one as it did allow Washoe to communicate with her companions.

• Washoe’s signs do not remain specific to their original contexts which would suggest that she has learned language.

• The Gardners are reluctant to say whether Washoe has language.

Evaluation - Methodology

Method : Case Study

• Advantage – allowed the Gardner’s to treat Washoe like a human child and create a “natural” human-like environment.

• Advantage – provided a lot of qualitative data.

• Disadvantage – how typical a chimpanzee was Washoe?

Evaluation - Methodology

The choice of sign language was good because it enabled Washoe to copy words that she would never be able to vocalise.

Washoe was able to use learned signs in a wide variety of contexts: "open" for example would be used with doors, tins and nuts showing she had learned language.

Evaluation- Methodology

Some researchers suggest that Washoe has not learned language because her signs were not spontaneous.

They also suggest that she only responded to prompts and she was not engaging in anything like human conversation.

Evaluation - Methodology

Reliability

• Three observers agreed on a sign.

• Fifteen days use.

• Use of box to test signing ability.

Evaluation - Methodology

Validity

• Observer bias – researchers influenced by relationship with Washoe?

• Was Washoe using language, or just responding to cues from researches?

• Is the Washoe study supported by other animal research?

Evaluation - Methodology

Ethical Issues

• Washoe taken out of her environment to satisfy human curiosity – is this right?

• Ethical to teach language to animals?

• Do the findings of this research justify depriving Washoe of her natural environment?

Write short sentences evaluating this study

• Method they actually used

• Validity

• Sample

• Ethics.

Evaluation – Alternative Evidence

• KEY QUESTION – can chimps learn and use a human language?

• Gardners didn’t want to get involved in philosophical debate.

• Happy that they could communicate with Washoe.

• Other research might tell us more about what chimps can do

Evaluation – Other Research

• Savage-Rumbaugh(1991) – 10 years of training Kanzi on a Lexigram.

• Kanzi learned some words observing his mother being taught so Savage-Rumbaugh kept the training similar to the environment a child would experience.

• Kanzi learned 200 words and understood simple rules (action before object) which suggests that chimps don’t simply learn signs.

• Bonobo chimp better at learning language!

Evaluation – Alternative Evidence

More Gardner Research. Moja, Tatu & Dar• All raised from new born• Different ages, so like siblings• In training, signs used for dialogue, rather

than simply for requests ( to avoid operant conditioning)

• Gardner argues that evolutionary proximity would suggest chimps could develop language.

Evaluation – Alternative Evidence

Terrace (1979). NIM CHOMPSKY

• Learned 125 signs and made different combinations.

• 20,000 combinations in 2 years

• Found difference with human child language.

• Concluded – Nim was not using equivalent of human language.

Evaluation – Other Research

Computer Language : ELIZA

• Computers can produce language in response to humans.

• Does this mean they can understand it?

• How does this relate to Washoe’s use of signs?