Language Development Lecture notes 1-7 PDF

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Lecture 1 – IntroductionWhy study the development of language?General Perspective:Learning Outcomes:A brief overview of language acquisiion: language learning starts in utero  infants and caregivers love to communicate (child directed speech)  sensitivity to emotional tone  6-9 months  onset of...

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Development and Disorders in Language in Children

Lecture 1 – Introduction Why study the development of language?

General Perspective:

Learning Outcomes:

A brief overview of language acquisition: 

language learning starts in utero

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infants and caregivers love to communicate (child directed speech)

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sensitivity to emotional tone

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6-9 months

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onset of babbling

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change in sound discrimination skill

11-12 months 

production of first word

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understanding of about 50 words

12-18 months 

rapid vocabulary development

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one word utterances

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e.g. development of ‘gaga’ to ‘water’

18 months onwards 

development of syntax (into middle school years), starting with telegraphic speech

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development of pragmatic competence

Theoretical Approaches: 1) Cognitive developmentalists 

language is only one facet of human cognition

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concepts are learned before language

2) Information theorists

Development and Disorders in Language in Children

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interested in neural architecture that supports language processing and language learning

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computer models

3) Social interactionists 

language as social interaction

e.g. role of child directed speech

What is special about language acquisition? 

species-specific

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universal: e.g.

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milestones

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occurs naturally

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over-generalisations of regular patterns

fast (?)

Implications for theories of language: 

neurological (and physiological) basis

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innate Language Acquisition Device?

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importance of cognitive development?

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importance of social development?

Biological basis of language: Structure and Development Brain Structure 

lateralisation for language in left hemisphere

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major language areas: Broca’s area, Wernicke’s area and arcuate fasciculus

Brain Development

Development and Disorders in Language in Children

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infants have fewer synapses than adults

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age 2: number of synapses that of adults

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age 4-10: many more synapses than adults

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15/16 back to level of adults >> this might explain critical periods for language learning

The FOXP2 Gene ‘KE’ family (Marcus & Fisher, 2003; Fisher & Scharff, 2009) 

“KE” family: almost half of the family has severe speech and language deficits (e.g. difficulty with comprehension, writing, poor grammar, and speech motor problems)

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not restricted to humans (but mutation)

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possible involved in development of proper sensorimotor coordination

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suggest that linguistic ability is at least partly innate

FOXP2 in Zebra Finches 

zebra finches (98% overlap with humans)

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active in area X in basal ganglia, especially during early life when song learning takes place

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injecting tailored RNA to inhibit expression of FOXP2 leads to garbled songs

FOXP2 in Mice 

engineered mice with the same mutation as KE family

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difficulties to acquire new motor skills

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altered alarm calls of mouse babies >> mutation of FOXP2 affects aspects of learning and speech

Functions of FOXP2 

activates and suppresses genes

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some target genes control brain development in embryos

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suppresses CNTNAP2, a gene involved in SLI and autism

Language Impairment of FOXP2

Development and Disorders in Language in Children

Meaburn et al. (2002): 270 4-year-olds with low general language scores no FOXP2 mutation Evans et al. (2015): 383 children, genome-wide analysis link between phonological memory and two other chromosomes (10,13) > not all language-impaired individuals have FOXP2 mutations

Can other species learn language? 

true language: 

productivity/generativity (part of syntax and morphology)

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symbolism

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displacement

Chimpanzees - Viki (Date) 

raised by Catherine and Keith Hayes,

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four words after 6 years (mama, papa, cup and up)

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vocal tract limits chimpanzee’s speech

Washoe 

Beatrice and Allen Gardner taught her American Sign Language (ASL)

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learned > 130 ASL signs

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sign combinations (e.g. ‘apple in hat’)

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no attention to word order

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grammatical structure questionable

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Signs often repetitions of what caretaker just used

Nim Chimpsky 

raised by Herbert Terrace

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combinations of 2 to 3 signs 

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‘eat Nim’ ‘Banana me eat banana’

no particular word order

Kanzi 

bonobo

Development and Disorders in Language in Children

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researched by Rumbaugh couple

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understands at least 500 spoken words

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comprehends word order and basic syntax (‘put jelly in milk’ or ‘put milk in jelly’)

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language of 2-3-year-old

Summary

Reading for Lecture 1:

Lecture 2A - Prelinguistic Communication

Development and Disorders in Language in Children

Overview: 

Genetic predisposition to learn language and the critical period for language acquisition

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Infant’s contribution to communication in the first 12 months

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Infant directed speech

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Non-verbal cues of communication and joint attention

Genetic predisposition for language learning 

learning only through interaction 

Genie, a child that grew up in isolation without being spoken to, only learned two phrases/words: ‘stopit’ and ‘nomore’)

Recap of Lecture 1:   

Genie – Child was raised in isolation without being spoken to. Only learned wo phrases words ‘nomore’, ‘stopit’. Suggests there is a critical time period for language acquisition.

Communication in the First Year of Life What is Communication? Do infants affect the environment in which they learn language, and how do they? Can adults communicate with children and how? 

broad definition of communication: to use a sound/sign deliberately as a signal

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behavioural indicators; To have communication you should have: 

eye contact

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consistency – specific sign/sound in the communication to understand consistency in the language

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pauses, waiting for reaction – chance to respond to the communication

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persistency - communication intentions, so persistently producing sound for communication and letting the other person know what you want.

Contribution of the infant to communication 

Newborn: 

head-turning to noise - reaction to voices

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is calmed by voice – usually the mothers voice

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can discriminate many sounds

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prefers mother’s voice (DeCasper & Fifer, 1980) can hear the mothers voice in the womb (Insert multisensory study)

Development and Disorders in Language in Children

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1-2 months: first signs of communication - smiles, cooing (vowel sounds produced from the back of the mouth e.g. aaa, ooo)

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3-7 months: different responses to different intonations (angry, friendly). E.g. They get happy when they hear friendly voices and sad when they hear angry voices. Babbling also starts, for example baba, dada etc.

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intentional communication emerges between 8-10 months (linked to cognitive development) 

8-12 months: interpretable reaction to some word. This suggests they can acknowledge the difference between words.

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~10 months: showing, giving, pointing. Pointing is precedes the first word because pointing indicates looking at something in that corresponding direction not the finger itself.  Therefore, intentional communication develops around 8 to 10 months.  This is linked with cognitive development and Theory of Mind: people have thoughts and goals that differs from their own.

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~12 months: 

recognition of 50 words

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production of first words

Pointing Observation: Pointing precedes the first word. When babies are first asked to point to an object it starts off as a reach, and then precedes into a point  the second time they are asked to point, they point straight away. What does this mean? Pointing precedes the first word and the Theory of Mind(ToM) Liszkowski (2006, 2008): Pointing in Infants to communicate. -

12-month-olds point to objects the experimenter needs. E.g. The experimenter is trying to open the file cabinet but drops the key, the experimenter cannot find the key but the infant can. The infant was able to point to the keys and show the experimenter. This implies 

understanding of the other’s intention – wanting to open the cabinet with the key and trying to look for the key.

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understanding of need for information – understood the experimenter cannot see the key but they can, and they need to show where the key is.

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understanding of effect of pointing (direct attention) - understand their ability to point to show where the key is.

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wish to share information / to help – understand they can share their knowledge the experimenter does not have.

Development and Disorders in Language in Children

Child-Directed Speech (CDS)/ Infant directed Speech / Motherese Video Observations: Effective communication between a adult and child includes exaggerated tones that can switch from high to low very quickly. A lot of repetition and pauses, the utterances are quite short – not to complex to understand. Properties of CDS I 

exaggerated intonation contour (e.g. more variable pitch and exaggerated stress in English): more variable pitch and exaggerated stress on certain sounds

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slower than speech to adults

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more immediate repetitions of words/phrases – help the child segment and learn the words. It also suggests the comprehension and production develop in parallel and comprehension of the words precedes production.

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smaller vocabulary – help the child to learn the language

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more diminutives (kitty, horsy etc.) or special words (choo-choo) – help the child to learn the language.

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shorter and syntactically less complex utterances

Properties of CDS II 

clear turn-taking – pauses, waiting for a response (can be verbal or nonverbal e.g. smile)

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clear eye contact and pointing – intense eye contact needed for child directed speech

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adaptation to child’s age – When a child is first born, the child directed speech is more complex and they use more words. When the child begins to understand some of these words the caretaker adapts the child directed speech for more effective learning. They use more repetition and smaller vocabulary. When the child starts understanding these words, they child directed speech will become more complex using a richer vocabulary and less repetition.  The child directed speech is like a U shape, with adaptation to the child’s age.  Universal  Most countries have child directed speech. BUT, does that mean Child Directed Speech is essential for the Language Acquisition? - Quiché Maya (South America) – does not communicate with an infant because they are not suitable in producing communication - Kaluli (Papua New Guinea) – Only communicates with the child using rhetorical questions YET the infants of these culture still reach the language acquisition milestones the same as other cultures using child directed speech. SUGGESTING child directed speech is not essential for language acquisition. 

HOWEVER > properties of CDS can in principle facilitate language learning.  What are CDS Properties…

Development and Disorders in Language in Children

Does CDS Facilitate Language Learning? 

some properties of CDS could support language learning 

prosody: change in intonation (the rise and fall of the voice) holds attention, marks syntactic and word boundaries (Thiessen, Hill, Saffran, 2005)

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repetition: supports lexical (lexical = words or vocabulary of a sentence) learning

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word order, putting new words in utterance-final position: supports word recognition

How much CDS does a child get? How much does a child need to benefit from CDS? Van de Weijer (1998): Investigated language input in infants 

continuous recording of all speech input to child between 6 and 9 months

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time awake: about 8 hours

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Results: language around them supports their work learning

Different measures of how caretakers communicate with an infant/child Weisleder & Fernald (2013) Cameras were attached to the baby to record how the baby is treated in the home. How much of the communication is speech related? The child was awake on average around 8 hours of the day, around 40% (20 mins) do caregivers use child directed speech. 30% was speech directed from the adult to a sibling of the infant. >50% was overheard speech between adults or from the TV, speech that was not intended to the child.  children do not benefit from overheard speech/ no relation to vocabulary outcome.  From 2013 to now, studies have shown children benefit from receiving =>20minutes of child directed speech are more efficient processing words.  Therefore, only infant directed speech contributed to word learning. BUT  most studies do not test cause-effect relation, only correlation  correlation may have been caused by confounds (e.g. CDS = happy talk, emotional talk, instead happy talk draws attention or high verbal IQ is mothers is passed to children)  assumed large variation in quantity and quality of CDS seems to lead to very little variation in linguistic skills

Non-verbal cues of communication (caretaker)

Development and Disorders in Language in Children

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clear pointing accompanying standard verbal cues, “look, this is ...” clear eye contact joint attention - when the caregiver and the child attend their attention to the same object.

Joint focus of attention  

listeners can, in principle, use information about the speaker’s point of gaze to identify a referent object this presupposes that children have Theory of Mind – caretaker has their own goals and thoughts.

Speakers usually use joint attention – they look at what they are talking about with both child and adult. Tomasello & Todd (1983) 

video-tapes of mother-child interactions (12 months - 18 months)

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time spent in joint attention episodes (only when mother responds to child’s attention) correlated positively with infant’s acquisition of object labels

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Two conditions: the child refers to an object and the mother follows behind. In the second condition, the child refers to an object and the mother shows a new object and the child redirect their attention to this new object

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Result: Only when mothers responded to the child’s attention did it positively create object labels. But when the child’s attention is redirected it is negatively associated with object labelling.

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BUT is this to do with language, or learning – when the babies attention is redirected it affects the learning?

Tomasello and Farrar (1986)- object labelling/ language learning in and out the language development episodes 

videotaping of mother-infant play at 15 months and 21 months

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more speaking from mother in episodes of joint attention than non-joint attention

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only joint attention correlated with lexical development with the object used

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This prelinguistic nonverbal communication helped language development in the child later on.

Tomasello and Farrar (1986) – Study II Attempt to understand - whether if a baby attends to an object for object labelling using joint attention – is it due to joint attention or because they like the object.

Development and Disorders in Language in Children

Why? Past results show children do not learn the names of other object when their attention has been redirected. Is this because they don’t like the object? Hypothesis: child-initiated joint attention may be more useful for word-learning than adult-initiated ones 

ten 14- to 23-month-olds infants

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teaching of 4 new objects across several attention episodes (joint attention vs redirected)

Conditions: 

follow-in for 2 of the objects the adult names object when child attends to it

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directed (redirected attention condition): adult holds up object and names it when child does not attend to it 

both conditions lead to learning, but follow-in condition to better learning

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If the child if focussed on one object to begin with, then the mother contributes by attending to the same object and naming it  leads to better object labelling.

Results: -

Therefore, joint attention lead to attention learning, it is not related to liking the object.

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from about 12 months, children check adult’s gaze direction when hearing new word   

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Suggests the child has some form of ToM They know the adult is not attending to the same object as themselves – they have other goals. They can join their gaze, but this comes with cognitive development and ToM

they do not assume that an adult refers to the object they themselves are attending to (Baldwin, 1991; Tomasello et al., 1996)

Lecture 2b – Phonological Development Overview: 

Infant speech perception (in the first 12 months)

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Prelinguistic vocalisation in the first 12 months.

Development and Disorders in Language in Children

When do infants recognise their own language/ Early language preference 

In the womb they have some acknowledgement of their own language prosody( high and low tones in vocalisation) BUT HOW DO WE KNOW THAT?

The HAS Paradigm 

HAS (High Amplitude Sucking) paradigm builds upon inf...