PSYCHOLOGY OF LANGUAGE

1. PSYCHOLOGY OF LANGUAGE Heather Ferguson

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

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

4. 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

5. 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

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

7. 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

8. 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)?

9. Testing Infants ba ba ba ba ba ba

10. Testing Infants ba ba pa ba ba ba

11. 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)

12. 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

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

14. 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

15. 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

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

17. 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

18. 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

19. 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

20. 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”)

21. 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

22. 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

23. 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

24. 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”

25. 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

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

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

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

29. 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

30. 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”)

31. 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

32. 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

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

34. 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

35. NATIVISM • Universal grammar: • 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

36. 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

37. 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

38. 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

39. 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

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

41. THE CRITICAL PERIOD HYPOTHESIS Eric Lenneberg, 1967

42. 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

43. 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

44. 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

45. CASE STUDY The story of Genie

46. 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?

47. 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

48. 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

49. 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

50. 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