GARDNER AND GARDNER OVERVIEW

Aims

aimed to see if they could teach a chimpanzee to communicate using a human sign language (asl) to raise a chimpanzee the same way as a child - to aquire language naturally.

Context

Chomsky (1957) humans have special part in their brain so animals cant aquire language

Hayes and Hayes (1952) taught vicki to produce vocal language - only aquired 4 words

G&G pointed out chimps cant aquire vocal language, they only vocalise in moments of stress or excitement and have a different vocal apparatus too humans.

Washoe was a wild caught female infant chimp, 8-14 months old. she was raised like a child. she was always with at least one of her companions who would always speak and play with her using ASL

TRAINING METHODS;

• immitation of signs- 'do this' copy and rewarded - not successful didnt do it on command
• prompting - if washoe did sign sloppilys - it was corrected
• using signs - during games and everyday routines - all objects were given a sign
• manual babbling - encouraged by repeating babble back and link it to signs
• operant conditioning - rewards so behaviour was repeated (tickling)
• shaping - rewarded for producing similar signs, then only rewarded for closer signs
• direct tuition - 121

FINDINGS

• aquired 30 words in 21 months - which met the strict criteria set by g&g
  • differentiating- washoe used the sign flower referring to odours, when smelling cooking, but g&g taught Washoe a new sign for smell- later learned to discriminate fairly consistently between the two signs.
  • transfer- learned to generalise a sign to a class of objects, to apply signs like flower to different flowers and dog when she heard dogs barking- not just seeing one.
  • combining- two or three signs such as 'listen dog' 'open food drink' 'go sweet'

CONCLUSIONS

• chimps can learn more than a few words
• sign language is an appropriate way of communication
• more can be accomplished, started to spontaneously transfer and combine

problems- used double blind to help reliability

design- case study

ethics- balanced; if animals use human language=more rights? but taken an animal out of its natural environment and doing tasks that arent natural, living in captivity.

reliability- strict criteria, all three observers had to see Washoe's sign spontaneously and appropriately.

validity- observer bias
    Clever Hans was just responding to trainers cues- was Washoe? 

FURTHER WASHOE RESEARCH - before she died 58 years later she knew 250 signs

MOJA, TATU AND DAR- raised by the Gardners(1989) same as Washoe but had company

LOULIS- washoes adopted son, only taught 7 signs- learnt 50 signs from other chimps

NIM CHIMPSKY- Terrace(1979) learnt 20.000 communications - not human language

KANZI AND MULIKA- learnt lanugage through use of lexigrams, Bonobo chimps, not specifically  taught to use the lexi grams, learnt through eachother (2500) Savage Rumbaugh concluded  some chimps have greater prosperity for language than others.

ELIZA- in 1960s Weizenbaum created a programme eliza, that was able to respond to a users input, judges couldnt always tell the difference between Elizas responses or a real therapist- suggesting there is a difference between being able to produce language and actually understanding it

STRENGTHS

• supports hypothesis that animals can learn a form of a human language
• appropriate learning environment
• similar hands - not limited
• researchers always spoke in sign language - like a child
• strict criteria improves reliability
• used double blind

WEAKNESSES

• little evidence to confirm washoe understood symbols
• ethical issues
• hard to generalise
• observer bias?
• validity- more understanding of structure