PSYCHOLOGY OF LANGUAGE Heather Ferguson

OVERVIEW Definition of language Stages of language perception Stages of language production Theories of language acquisition Critical period hypothesis Case study Bilingualism

WHAT IS LANGUAGE? ‘The systematic, conventional use of sounds, signs, or written symbols in a human society for communication and self-expression.’ David Crystal

STAGES OF LANGUAGE PERCEPTION At birth Already prefer the sounds of their mother’s voice Can discriminate between mother’s native language an other languages

Discriminating sounds Adult speakers have difficulty discriminating between language sounds that are not phonemic contrasts in their native language Young infants do not demonstrate this difficulty initially They can discriminate any contrasting phonetic sounds in the world’s languages

How can we possibly know that? Are /s/ and /ç/ different sounds for you, baby?

Testing Infants Some helpful things infants do for experimenters: They look longer at new stimuli compared to familiar stimuli They suck faster when exposed to new stimuli

Testing Infants Habituation-dishabituation method Habituate infant on one stimulus Show new, different stimulus Does the infant react to the new stimulus as new? Habituation-dishabituation measures Time looks to stimulus High-amplitude sucking paradigm Does the infant start sucking faster on a pacifier (that’s hooked up to a monitoring device)?

Testing Infants ba ba ba ba ba ba

Testing Infants ba ba pa ba ba ba

Limited-time Offer However, infants can only discriminate all phonemes for a limited period of time At 4 to 6 months phonetic sensitivity diminishes. By 12 months, infants are very poor at distinguishing foreign contrasts The (speech) perceptual system is being reorganized around these time periods (4-6 months & 10-12 months)

Theory Exposure and habituation to the sounds of the target language impedes an infant’s ability to perceive phonetic contrasts that the native language does not make There are innate language abilities that are lost due to experience with a first language One is born with all language sounds available, but sound distinctions are lost as sound system develops

Phonemic Organization Account Loss of perceptual ability is related to development of phonemic categories for the first language- phonemic organization

Infant-directed Speech 7-week-old infants prefer infant-directed speech (‘motherese’) to adult-directed speech Regardless of gender of speaker Older infants show this preference as well, but younger infants are more responsive, both in terms of attention and affect

STAGES OF LANGUAGE PRODUCTION The larynx At birth- the larynx is relatively high, and entire vocal tract is quite different from adults At 3 months- larynx begins to descend (won’t reach adult location until ~3 years old) At 4 months- the vocal tract begins to resemble an adult vocal tract

Infant Speech Production Because of their maturing vocal tract, some sounds are genuinely difficult for young children to produce

Stage I (0-8 weeks): Basic biological noises Reflexive Hunger, pain and discomfort resulting in crying Vegetative Sucking, swallowing, coughing, burping Airstream mechanism and vocal folds used to produce pitch patterns in a rhythmical fashion

Stage II (2-5 months): Cooing and laughing Cooing sounds develop alongside crying Quieter, lower-pitched and more musical than crying Short-vowel-like sounds preceded by a consonant-like sound produced at the back of the mouth No rhythm or intonational contour Laughing sounds emerge at around 4 months

Stage III (5-7½ months): Vocal Play High-pitched segments over one second long, frequently repeated (longer in duration than cooing) Wider intonation ranges (low to high) Large inventory of consonant and vowel sounds, with periodic focus on particular places of articulation

Stage IV (~6-12 months): Babbling Features of babbling: Sounds are a subset of possible sounds found in spoken language Syllabic organisation Reduplication Same two sounds repeated (“babababa” “papapapap”) Variegated babbling (~12 months) Sounds change between syllables (“bamipabo”)

Stage IV (~6-12 months): Babbling Features of babbling: Lack of meaning/ reference Rhythm and intonation reminiscent of speech Continuity of phonetic form and syllable type between a child’s babbling and first words Infants will often seem to ‘practise’ when alone Suggests that babbling is related more to practising speech sounds than communication

Babbling & Sign Language Deaf infants also babble Often delayed (11-24 months) compared to hearing infants Often different in character (e.g. fewer different kinds of consonants) This indicates that exposure to a spoken language influences babbling Infants (hearing and deaf) who are exposed to sign language will babble manually

Stage V (9-18months): Melodic Utterance Variations in melody, rhythm and intonation become a major feature toward the end of the first year Begins to sound language-like

First Words Around 12 months Focus on words related to the here and now, concrete things: People’s names, toys, clothes, food they eat Words for things that they can influence (one-word stage) “ball” likely to be learned earlier than “chair” or “tree”

First Words Two kinds of errors children can make: Overextension- refer to all four legged animals as dogs Underextension- refer to only the family dog as dog

The Mapping Problem Child says “What’s that?” and points to: So…how could this possibly go wrong?

The Mapping Problem Potential problems: More than one referent could apply to the word, “teacup”

The Mapping Problem Potential problems: More than one word may apply to a referent: Tea? Teacup? Saucer? A drink? Cup?

The Mapping Problem Apparent solutions: Whole object bias- children prefer to attach new labels to the whole object Mutual exclusivity bias- children prefer to have only one name for an object

Early “Multiword” Utterances By about 15months babies have a vocabulary of about 20- 25 words Two years Vocabulary rapidly increases to 100’s of words Child constructs primitive sentences- two-word stage (“no eat, throw ball”)

Early “Multiword” Utterances Thirty months Utterances progress beyond 2- word stage and show basic propositional structure (telegraphic stage) Functional words appear (“the, in, of”) Children overgeneralise rules (“goed”) Five years old Basic structure of language is in place Vocabulary of 10000- 15000 words

THEORIES OF LANGUAGE ACQUISITION Nativist Theories Language is entirely innate Learning Theories Language is entirely learned Cognitive Theories Language development is related to other cognitive developments Social Interactionist Theory Language is acquired through communicative interaction

NATIVISM Emphasizes a child’s inborn capacities for language Language is acquired through a genetic program Language acquisition is distinct from other cognitive processes

NATIVISM Noam Chomsky- the language acquisition device (LAD) Children are born with a basic understanding of language and a mental capacity to learn it quickly Brain is ‘over- connected’ at birth. Connections that are not used die or become dormant, and new connections based on experience form There is a specific time period of function

NATIVISM Universal grammar: Key assumption: Children are pre-programmed with a kind of default language which can be altered with exposure to a specific language Key assumption: Infants develops language even when other cognitive skills are low

Evidence in Favour of a Pre-determined Biological Language System: Other primates don’t learn language simply by being treated like human infants Gua (chimp, 1993) Raised alongside a 9½month-old boy for 9 months Never spoke but learned to comprehend spoken requests Viki (chimp, 1951) Raised alone from 3 days- 7 years old Capable of picture recognition, sorting of pictures and objects into conceptual categories Understood large number of words and phrases But, comprehension contextually determined

Evidence in Favour of a Pre-determined Biological Language System: Children with other cognitive deficits still learn language Language skills can persist even in cases of profound mental retardation

Evidence in Favour of a Pre-determined Biological Language System: Poverty of the stimulus Language input to children is ill-formed and incomplete (motherese) Children don’t receive explicit rules about what not to do They don’t get it even if you do tell them

Evidence in Favour of a Pre-determined Biological Language System: Creoles Pidgins develop in language contact situations (mostly colonial) (Pidgin = a language that has been constructed from two or more shared languages for communication between communities. A pidgin is not a mother tongue) Creoles develop from children exposed primarily to pidgins (Creole = a language that has developed from a mixture of languages) Children are, in essence, filling the gaps of pidgins

Evidence in Favour of a Pre-determined Biological Language System: Evidence for critical period of language acquisition

THE CRITICAL PERIOD HYPOTHESIS Eric Lenneberg, 1967

THE CRITICAL PERIOD HYPOTHESIS Lenneberg theorized that… The acquisition of language is an innate (you are born with it) process Biological factors limit the critical period for acquisition of a language to a ‘window of opportunity’ from roughly two years of age to puberty If a child does not learn a language before the onset of puberty, the child will never master language at all

Bird Song and the Critical Period Hypothesis Some birds (like Sparrows) have courtship songs Songs have dialectal variation Individual song is a version of other songs it hears during the ‘critical period’ of first 100 days of life Bird learns song by trial and error (babbling) When deprived of song input early in life, they fail to produce a normal song

THE CRITICAL PERIOD HYPOTHESIS The critical period and the human brain… Lenneberg believed that after lateralization (a process by which the two sides of the brain develop specialized functions), the brain loses plasticity Lenneberg claimed that lateralization of the language function is normally completed at puberty, making post-adolescent language acquisition difficult

CASE STUDY The story of Genie

The Story of Genie Read about Genie and decide for yourself… How does Genie’s language development relate to Lenneberg’s theory? What is the strongest evidence in support of the Critical Period Hypothesis Was Genie’s early language deprivation the ONLY thing that contributed to her abnormal language development?

The Story of Genie Main points… From 20 months- 13 years old Genie was not allowed to make noise and was not spoken to (father barked or growled at her) When found could not speak or understand words (except name and ‘sorry’) Over time, vocab increased and she learned to speak in 2/ 3- word sentences BUT, speech has remained garbled and she has never mastered grammar needed for language

Genie and the Critical Period Hypothesis At first, a number of researchers thought that Genie would prove Lenneberg’s theory wrong as… 1 year after her escape she was producing 2/ 3- word sentences She could distinguish between singular/ plural nouns and positive and negative sentences Genie’s language resembled that of a normal 18- 20 month old child

Genie and the Critical Period Hypothesis BUT, As time went on, Genie’s vocab did not ‘explode’ as is the case with normally developing children Four years later… She still had not mastered grammar She could not ask questions properly (“where is may I have a penny”) She confused pronouns, using ‘you’ and ‘me’ interchangeably

Genie and the Critical Period Hypothesis Has Genie supported Lenneberg’s theory? NO! Why? Genie’s personal history was so disastrous that it is not clear why she did not make progress with her language It is possible that Genie did not master language because she had passed the ‘critical period’ BUT, other explanations are available

Genie and the Critical Period Hypothesis Genie’s brain may have been abnormal Brain scans showed that Genie’s brain was unusual As we know, for most people, the areas of the brain responsible for language functions are located in the left hemisphere BUT, Genie’s brain was dominated by the right hemisphere

Genie and the Critical Period Hypothesis Conclusions… Genie’s lack of progress does suggest that, over a certain age, any child who has not learnt a language will have difficulty acquiring one BUT, other explanations can not be ruled out Therefore, Lenneberg’s hypothesis is not proven, but it is strongly supported

LEARNING THEORIES Associated with Skinner, Pavlov, etc Language is learned through basic processes like associations, reinforcement and imitation Language acquisition occurs through three processes:

LEARNING THEORIES Classical Conditioning US UR US + CS CR “bottle”

LEARNING THEORIES Operant Conditioning Reinforcement/ rewards Children are rewarded for early attempts at language Selective reinforcement shapes children’s language as the requirement for a reward becomes more specific

LEARNING THEORIES Social learning Observation and imitation of others, especially those who are powerful, nurturing and similar to the child

Limitations of Learning Theories BUT, these processes can not fully account for language development in children because… Not enough to explain the complexities of language itself Most parents do not consistently reinforce proper speech Children say things they would not have heard an adult say Aspects of language development are universal and do not vary with different experiences

COGNITIVE THEORIES Language is unique to humans But, not a modular, pre-programmed ability General disposition for learning that allows language Pattern recognition Imitation Language development is related to other forms of development For these kinds of theories to be true infants must have general skills that clearly contribute to language

Cognition and Language Cognitive skills that are not language specific but none-the-less contribute to language Newborns prefer face-like to non-face-like stimuli Quickly learn to recognize their mother’s face Young infants focus on the eye region more than other facial regions More inclined to look at a pleasantly moving face than a still one

Cognition and Language Infants know much more than they can demonstrate physically So, infants come to the language environment with a much more sophisticated view of the world than has been previously thought LAD not necessarily needed!

INTERACTIONIST VIEW Both inborn capacities and learning are important Emphasizes the use of language and the fit between the child and the language environment Jerome Bruner- the language acquisition support system (LASS) Social context of language development is important Language- skilled adults structure and support the child’s language learning environment

INTERACTIONIST VIEW Parent- child language interaction characterised by: Infant- directed speech (‘motherese’) High- pitched, simple, redundant speech adults use with babies Recasting Rephrasing what child says, often as a question Echoing Repeating what a child says Expanding Restating in a more advanced way what a child says Labelling Naming objects

SUMMARY OF THEORIES OF LANGUAGE ACQUSITION Language is clearly genetically specified It appears that only humans develop a full version of it But not yet established to what extent language is directly specified and to what extent its development is tied up with other aspects of cognitive and social development

BILINGUALISM

Bilingualism and the Critical Period Hypothesis What is a bilingual? A person who uses or is able to use two languages, especially with equal fluency Is there a cognitive advantage to bilingualism? Early studies showing a disadvantage Studies of immigrants Confounded by social class Later studies showing an advantage Avoided social class confounds Picked up new confounds eg. ‘who is bilingual?”

Bilingualism and the Critical Period Hypothesis Evidence for… It is significantly harder for older adults to master a second language Evidence against… Some late L2 learners can become ‘perfectly fluent speakers’ (Long, 1990; Birdsong, 1992)

Brain and Bilingualism: Issues Are the separate languages of bilinguals stored in separate parts of the brain? Does neural representation vary with age of acquisition? Is there a “language switch” somewhere in the brain?

Brain and Bilingualism Mixed evidence for differing brain regions in early and late bilinguals… Some studies have found similar patterns in early and late bilinguals (Chee et al., 1999b)

Brain and Bilingualism But, some fMRI studies have found different patterns of activation in sentence production in early and late bilinguals (Kim et al., 1997)

Bilingualism Conclusions The two or more languages of bilinguals are distributed across the same brain regions that are used by monolinguals (Broca’s and Wernicke’s) For both monolinguals and bilinguals, the regions involved in language use vary by task, expertise and strategy The same areas may have to “work harder” and additional areas may be recruited for processing in the weaker language Second language learning appears to be easier in the critical period than later in life, BUT it is possible to become fluent in a second language Second language is not necessarily the weaker language!

LANGUAGE REFERENCES Gleitman, H. 1999: Language in Psychology. Chapter 9, pp 344- 399 www.feralchildren.com Bee, H. The developing Child