COMPARATIVE PSYCHOLOGY • THE STUDY OF ANIMAL BEHAVIOUR • CHARLES DARWIN • THE EVOLUTION OF THE SPECIES • we all evolved from a common ancestor
COMPARATIVE PSYCHOLOGY • THE STUDY OF ANIMAL BEHAVIOUR • Humans share many behaviours with non-human animals • But what about language? • What is language?
Language…. • How is it that we are able to speak? • Do we learn? • Or • Is language innate? • An example of the nature nurture debate
Language theories…. • The behaviourist theory (Skinner) • That children learn by • Imitation • and • Reinforcement • operant conditioning…
Language theories…. • The nativist theory (Chomsky) • That children are born with an • Innate Language Acquisition Device • LAD • that the ability to use language is hard wired into the brain
Language theories…. • Nurture (Skinner) • This theory emphasises performance • a child imitates what she hears and is reinforced when correct • gradually vocalisations are shaped and words are learned
Language theories…. • Nurture (Skinner) PROBLEMS • It would take too long • Parents do not reinforce correct speech
Language theories…. • The nativist theory (Chomsky) • emphasises the difference between • performance vs competence • using vs understanding • All humans are ‘prepared’ to learn language • All normal children acquire language in similar stages • Linguistic universals exist in every language
LINGUISTIC UNIVERSALS • Language not just a mish mash of sound • THREE COMPONENTS of language • PHONOLOGY - SOUND PATTERNS • SYNTAX - WORD PATTERNS • SEMANTICS - MEANING PATTERNS
LINGUISTIC UNIVERSALS • SEMANTICITY - words have meanings • DISPLACEMENT - the ability to use words to refer to things that are not present in time and space • STRUCTURE DEPENDENCE - words can be ‘chunked together’ and moved around - • the policeman shot the man in the garage • CREATIVITY - each sentence that is spoken might be a unique ‘utterance’ • GENERALISATION - from one situation to another
Language --- the great debate • Why teach language to apes? • THE RATIONALE • If apes can learn language it supports Skinner (Nurture) • If not • Perhaps Chomsky was right (Nature)
Teaching language to apes • The earliest experiment • The Kelloggs and Gua • brought up like human baby • continually exposed to speech • ‘understood’ 70 words but never spoke • Chimps do not have vocal chords that can produce speech
Teaching language to apes • Premack taught Sarah (1966) • trained by Operant Conditioning • lived in a cage • taught to manipulate symbols on a plastic board • e.g. RED SQUARE meant banana • could ‘understand’ and follow orders • never initiated word games
Teaching language to apes • Savage Rumbaugh taught Lana • funded by Coca Cola • symbolic keyboard linked to computer which is linked to a vending machine • If Lana requested ‘food’ she received it • Lana understood arbitrary symbols like ‘more’ • YES - semanticity YES - displacement, • NO - structure dependence
Gardner & Gardner (WASHOE) • Method - a case study • Participant - a female chimp WASHOE • Age - approx I year old • Procedure - Washoe lived in a caravan in the Gardner’s garden • Never alone when she was awake • team of researchers and psych students
Gardner & Gardner (WASHOE) • How was Washoe talked to? • American Sign Language (ASL) • Signs stand for words • Washoe continually surrounded by ‘signing humans’ • No rigorous training methods • No other ‘language’ used
Gardner & Gardner (WASHOE) • Training methods • Imitation • Babbling • Instrumental conditioning
Gardner & Gardner (WASHOE) • Imitation. • As with chimpanzees in general, Washoe naturally imitated. Washoe signed the sign for 'toothbrush' spontaneously upon entering the Gardener's bathroom and noticing toothbrushes. There seems to have been no obvious motive, except to communicate.
Gardner & Gardner (WASHOE) • Babbling. • 'Babbling' here does not mean vocal babbling, rather the untaught signs used by Washoe to communicate a desire. Washoe used a begging gesture, which was not too different from the ASL signs for 'give me' and 'come'.
Gardner & Gardner (WASHOE) • Instrumental conditioning. • Humans could not learn a language, purely by instrumental conditioning, although it seems likely that the 'trick vocabulary' of early childhood could be acquired in this way. Instrumental conditioning was one strategy used with Washoe. Tickling was used as a reward. The sign for 'more' was learnt by instrumental conditioning. This sign was later applied to a variety of relevant situations.
Gardner & Gardner (WASHOE) • How did they measure what Washoe had learned (the DV) • A sign was assumed to be learned • IF • Washoe spontaneously used a new sign, seen by THREE observers and used over 15 days
WASHOE’s progress • First SINGLE WORDS • come, gimme, hurry, sweet, tickle • 34 after 21 months • by 4 years over 100 signs • YES - SEMANTICITY • signed TOOTHBRUSH in bathroom • signed FLOWER in garden and when shown picture of flower
WASHOE’s progress • YES – GENERALISATION (or Transfer) • MORE - first used with TICKLE • then - generalised to MORE • e.g. food, drink, pushing in laundry basket
WASHOE’s progress • DISPLACEMENT • YES • WASHOE could refer to absent objects and people
WASHOE’s progress • Differentiation. • The sign 'more' used in many different situations until a more specific sign had been learnt. The sign for 'flower' used inappropriately for the idea of 'smell'. After additional training eventually Washoe was able to differentiate between 'smell' and 'flower'.
WASHOE’s progress • CREATIVITY (combinations) - YES • Washoe spontaneously used combinations of signs • GIMME TICKLE - come and tickle me • OPEN FOOD DRINK - open the fridge • LISTEN EAT - listen to the dinner gong • GO SWEET - take me to the raspberry bushes
WASHOE’s progress • NO - STRUCTURE DEPENDENCE? • English children usually put the • SUBJECT before the ACTION • Mummy come • Eve read • Car gone
WASHOE’s progress • NO - STRUCTURE DEPENDENCE? • Washoe did not seem to do this • GO SWEET or SWEET GO • meaning take me to the raspberry bushes • Why might this be?
WASHOE’s progress • WHY NO STRUCTURE DEPENDENCE? • Perhaps the researchers were overeager and gratified her every whim thus she did not need to learn about word order - • perhaps if she had had difficulty making herself understood she might have learned structure
WASHOE’s progress • WHY NO STRUCTURE DEPENDENCE? • It may be harder to maintain a fixed sequence with signs, some research suggests that deaf adults are not always consistent in ordering sign language
WASHOE’s progress • WHY NO STRUCTURE DEPENDENCE? • Perhaps she would have learned eventually • BUT - perhaps she did not and could not understand the patterned nature of language
WASHOE’s progress • WHY NO STRUCTURE DEPENDENCE? • Also perhaps the ‘researchers’ were not very good signers!
WASHOE’s progress • WHAT else HAPPENED TO WASHOE • She was allowed to adopt a young chimp - LOULIS • She ‘signed’ to LOULIS • CHAIR SIT - sit on the chair • FOUTS 1983 reported • “through imitating Washoe, Loulis now has his own repertoire of signs”
WASHOE’s progress • SUMMARY - can WASHOE use language? • SEMANTICITY- YES • DISPLACEMENT - YES • STRUCTURE DEPENDENCE - NO • CREATIVITY - Some but limited • GENERALISATION - YES • The GARDNERS said YES
WASHOE - CRITICISM • BY TERRACE (Nim Chimpsky) • Difference between children and NIM (and WASHOE) • No increase in length of sentences • Increase in imitation which decreases in children
Training techniques • Imitation (e.g. toothbrush) • Babbling (e.g. bits of natural actions moulded into signs – like gimme • Instrumental conditioning (e.g. more)
WASHOE’s CRITICISM • BY TERRACE (Nim Chimpsky) • Only 12% of NIMs utterances were spontaneous BUT children do not only talk when prompted • Nim (& Washoe) never learned to ‘take turns’ when talking - never learned the rules of the ‘language game’
WASHOE - CRITICISM • NOAM CHOMSKY • “It is about as likely that an ape will prove to have language ability, as that there is an island somewhere with a species of flightless birds waiting for humans to teach them how to fly”
Gardner & Gardner (WASHOE) • Ethics - how might you criticise this case study? • Generalisation - can the findings of this study be generalised to all chimps? • Why or why not?
Gardner & Gardner (WASHOE) • Questions • Describe some examples of animal communication • Describe some forms of human communication that do not use language
Gardner & Gardner (WASHOE) • Questions • Describe the strengths & weaknesses of the case study method? • What do you think might be the main difficulty in recording sign language in a chimp?
Gardner & Gardner (WASHOE) • Questions • How do people KNOW when it is their turn to speak in a conversation? • IMPLICATION: • If Washoe can be shown to have learned language which theory SKINNER or CHOMSKY is supported?
Gardner & Gardner (WASHOE) • Application - how is this study useful? THE END