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Some definitions
Language - a socially shared code or conventional system for representing concepts through use of arbitrary symbols and the rule governed combinations of those symbols – Speech - a verbal means of communicating or
conveying meaning Gestural precursors to speech – and gestural forms
of speech
Questions 1
List and describe the two functions of crying? List and describe the major stages of pre-speech
vocalizations—phonation, cooing, expansion, canonical babbling, and integrative—using the audio samples from class as examples.
What types of vocalizations are produced in the expansion stage, why might infants produce them, and what are infants doing in producing them that (most) other animals cannot do?
What are characteristics of first words and what is the timetable for their emergence?
5
Crying
Earliest vocalization –Curvilinear development at birth cry 1-1 1/2 hrs/day 6 wks cry 2-4 hrs/day 12 wks crying decreases Individual differences in quantity
Naturally occurring behavior– Then recruited for communication– Continuum of intentionality– Both directed and undirected crying still present at 12
months
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Two crying functions
“[N]aturally occurring cry in 26 infants – (aged 2.8-13.2 mo) and their mothers at home.
By 12 mo, most infants sometimes directed their crying toward the caregiver and elaborated the sounds by the use of gestures.
– But most continued to exhibit simple, undirected crying. Crying is both intentional and not intentional Shows increasing variability and sophistication in form
and function. • Gustafson, G E.; Green, J A. Developmental coordination of cry
sounds with visual regard and gestures. Infant Behavior & Development. 1991 Jan-Mar Vol 14(1) 51-57
7
Different acoustic patterns
Basic hunger cry– rhythmic pattern of loud crying, silence, inhalation
Pain cry – loud, long shrill cry, then breath-holding silence
Fake cry low pitch and intensity, poorly articulated moans
8
Crying judgments
Adults have some capacity to distinguish Judgment depends on care giving context as
well as acoustics Perceived aversiveness is important
dimension of judgments about meaning of cries
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Cries sound bad
There appears to be an underlying continuum of perceived aversiveness in young infants’ cries
That can be predicted by their duration, dysphonation, and proportion of energy in various frequencies
Parents and undergraduate non-parents perceive the cries as equally aversive.
• Gustafson, G. E.; Green, J. A. ‘Acoustic features of cry perception: Infant development. ’Child Development. 1989 Aug Vol 60(4) 772-780
Prelinguistic speech
Use of sounds in a communicative manner before speech (no words or grammar)
Progress through stages culminating in speech-like vocalizations– Phonation, Gooing, Expansion, Canonical
Some overlap in vocalizations characteristic of stages
• Kim Oller
Phonation Stage, 0-2/3 months
Vowel-like (“quasi-resonant”) Produced with normal speech like phonation
involving vibration of the larynx but with the vocal tract at rest– “comfort or pleasure” sounds - can sound like grunts
The infant’s tongue almost completely fills the mouth limiting the sounds newborns can make
Cooing/Gooing Stage, 1 - 4 months
Still vowel-like– /e/ & /u/ – but last longer
more guttural & throaty– produced in the back of the vocal cavity
thought to be precursors to consonants– /k/ /g/
Expansion Stage, 3 - 8 months
Isolated vowel-like sounds – Usually produced with the mouth open – Full vowels (“fully resonant nuclei”)
Vocal repertoire expands dramatically Infant experiments with sound production, varying pitch,
volume, & rate
Intentional communicative play– Already beyond pre-set animal calls
Which have set form and set causes
– Infant vocalizes for pleasure (just to have fun) or displeasure
Checking out the new sound system
Yells/whispers: playing with amplitude/intensity yells = high intensity, whispers = low intensity
Squeals & Growls: playing with pitch– squeals = high pitch, growls = low pitch
Raspberries – labial trill & vibrants
Cannot transcribe as adult syllables
Marginal babbles– consonant-vowel (CV) sequences – the transition between C & V is slow and drawn out– immature syllables
Functional flexibility of infant vocalization. Oller, et al. 2013. PNAS
‘Three types of infant vocalizations (squeals, vowel-like sounds, and growls) express a full range of emotional content—positive, neutral, and negative by 3–4 mos.– Contrast: cry and laughter are species-specific
signals apparently homologous to vocal calls in other primates, show functional stability, with cry overwhelmingly expressing negative and laughter positive emotional states.’
16
‘Functional flexibility is a sine qua non in spoken language Appears before syntax, word learning, and
even joint attention, syllable imitation, and canonical babbling. The appearance of functional flexibility early in the first year of human life is a critical step in the development of vocal language and may have been a critical step in the evolution of human language, preceding protosyntax and even primitive single words.’
17
Canonical Babbling Stage, 6-10 mos
CV sequences – /ma/ /da/ /ada/
Transition between CV are crisp – Sounds like natural syllables in parent’s language– Parents good at identifying this stage
Reduplicated babbling – /baba/ /dadada/ /mama/
Importance of Babbling
Involves increasing control over the articulatory mechanism
Important pre-speech developmental milestone Should be present by 10 months!
– Occurs in Down Syndrome, premature, low SES kids and in all cultures
– But its delayed in hearing impaired infants and deaf children
20
Limitations of Babbling
At end of stage, infants begin to use patterns or rising intonation that resemble adult speech– also known as gibberish, jargon, or conversational
babbling– It has intonation contours of language being learned – Infants learn the music before the words
Does not refer (to objects, people, etc.) Is not language
21
Integrative stage (9-18 months)
Beginning of meaningful speech Some mixing of babbled utterances and
words Gibberish: (jargon) use of adult intonation
patterns but what they say makes no sense– sounds like the child is having a conversation
but you can’t understand what they are saying
22
First word definitions
Function– They are first words because they refer– Arbitrary sound is paired with an object– Often but not always nouns in the environment
23
First Word Characteristics
Form– Conventional– Typically brief
1 syllable, e.g., ‘no’ or a reduplicated syllable, e.g., ‘ma-ma’
Most linguistically common words– May be developed by babies– And may be the easiest to articulate
24
First Word Timetable
Appear– Typically: 11 to 13 months– Normal range: 10 to 14 months
Normal variation– 13 month vocabularies: 0 - 45 words– Should have first word by 15 months
Screen for delay
25
First 50 words
Represent all of the major grammatical classes found in adult language
- nouns: dog, cookie- verbs: down, up, eat- adjectives: hot, dirty- social words: yes, no, please- sound effects: meow, ouch, uh-oh
28
How words are learned
Reference: Pairing of object names with objects Child must visually attend while label is provided
– So receptive joint attention helps– Helps if parent labels what child is already looking at– May be facilitated by routines
Metalinguistic insights – “Things have names” “I can make things happen with
words”– Corresponds to vocabulary spurt
Rapid, accelerating growth
29
Nouns
Most common throughout language development
Why do infants learn nouns most rapidly?– Adults tend to label objects more than they
label actions (fly, run) or describe objects (yellow crayon)
– Verbs are conceptually more complex; nouns are concrete where verbs tend to be more
abstract
30
Vocabulary Growth
Slow at first– can take 3 or 4 months after first words to
achieve a vocabulary or 10 to 30 words 18 month infant
– typically has a vocabulary of 50 words 18 - 22 months
– Vocabulary spurt – From 50 to 300 words in few months
31
Meta-linguistic insights
Things have names” Corresponds to vocabulary spurt
Rapid, accelerating growth
“I can make things happen with words”– Effort to express/understand participate– Intentionality model (Bloom)
Language learning is effortful
Receptive and Expressive
2 types of vocabulary development– Receptive - understands others’ words
Say ‘bye-bye’. ‘Where’s Daddy?’ 13 months - 50 words
– Expressive - total words used (productive) Receptive typically outpaces expressive
– Child understands more words than they use
33
Individual Differences
2 styles of language– Referential style - use language primarily to
label objects in their environment E.g., dada, doggy, baba
– Expressive style - use language as a means for engaging in social interaction
Hi, bye, ut-oh– More kids have an expressive style although
most have a combination
34
Syntax = grammar
Evidence of syntax – Nonrandom combinations
Development of syntax– Takes place with no explicit instruction.
Parents may teach new words but don’t teach syntax. `The emphasis is on what the child is saying rather than how
the child says it.
Innate or modeled?
Syntax of one word speech
Holophrase - a single word used to express complex meanings– “Cookie” = “Give me the cookie” – Early utterances are telegraphic
The essential words are used to convey whole ideas
36
Syntax of 2 word sentences
Emerge – 15 – 24 months, mean is 18– Usually have 50 words in vocabulary before combining
words 7 months after their first words
First sentences typically consist of nouns, verbs & adjectives
– Uses: name, locate, negate, question, etc.– Pivot word
frequently occurring word attached to a variety of other words More: Mommy, milk, hug
Common Errors
Underextension– Word refers to particular exemplar– “Car” = family’s car
Overextension– Word refers to inappropriately large class– “Car” refers to all big things with wheels
Interplay between two yields correct word usage
38
Measuring grammatical development Mean length of utterance (MLU) is a measure of
syntactic development. Average length of the child’s utterances is
calculated in morphemes - NOT WORDS– a morpheme is the smallest unit of meaning in a word
free morpheme: can stand as a word by itself (e.g., kind) bound morpheme: exists only within a word (e.g., -ly, -ness, -
s, -ed, ‘s) Each new morpheme reflects new linguistic knowledge. “I running” = 3 morphemes (not 2 words)
39
MLU length
Children who have similar MLUs are at the same level of linguistic maturity, and their language is at the same level of complexity.
Children have MLUs of 1.0 to 2.0 1-2 years 2.0 to 3.0 2-3 years 3.0 to 4.0 3-4 years
Motherese/child directed speech
Most adults can do it, infants prefer it Parents speak for children Parents stay a step ahead of child (scaffolding) Aids in teaching the child the norms of their
culture & rules of their language – cultural differences stem from mother’s styles of
interactions and child rearing beliefs
Has positive affect on early language development
Infant directed speech
Slower rate, higher pitch, longer pauses– Repetitive & reduplicated
Brief, grammatically correct sentences– Use of simple syntax
Key words at end & are spoken in a higher & louder voice– Diminutive used
Vocabulary is concrete– Objects may be over described
https://www.youtube.com/watch?v=cSCXMfeo74Q
44
Children’s early comprehension of syntax Assessment methods involving action such as
– diary studies (parents document conditions under which the child can or cannot understand)
– act-out tasks (in which the experimenter asks the child to act out a sentence using toys)
– direction tasks (in which the child is asked to carry out a direction, such as “tickle the duck”)
– picture-choice tasks (in which the child must select the picture that best represents the linguistic form being tested)
Have limitations leading to confusion about children’s comprehension abilities.
45
The preferential looking paradigm Has helped clear things up.
– Used to assess language comprehension in infants as young as 12 months.
– Child watches two simultaneously presented videos. – Child hears a statement describing one of the videos – Record the amount of time the child spends watching
each video– Repeat
46
Child hears
“Cookie Monster is tickling Big Bird” – one screen showed Cookie Monster tickling Big Bird – One screen showed Big Bird tickling Cookie Monster.
Children at 17 months of age spent more time looking at the screen that matched the statement.
Children can comprehend word order before they even begin using two-word sentences.
Suggests that comprehension is indeed in advance of production, as parents have always known.
51
Learning Theory
Language is learned through experience. Emphasis on role of child’s environment– Reinforcement ~ Parents reinforce or reward infants
babbles that are approximations of real words (B.F. Skinner).
shaping ~ children acquire early vocabularies through shaping or when parents require children’s utterances to be progressively closer to real words before reinforcement
role of imitation ~ parents serve as models & children learn language in part through observation & imitation (Bandura)
52
Learning theory cannot explain:
why children spontaneously utter words or phrases they have never heard
why there are invariant sequences of language development
why there are spurts in language acquisition
Nativist Theory
Innate factors cause children to attend to & acquire language– Chomsky’s psycholinguistic theory
Environmental regularities cannot account for the consistency of language acquisition.
A neurally based language acquisition device is at work, enabling innate understanding of deep structure of language.
Evidence for an inborn tendency:
Verbal function is localized in speech centers– Typically in left cerebral hemisphere– There is plasticity– But it diminishes with age– Sensitive period ~ proposed by Lennenberg; beginning at 18-24
months & lasting until puberty neural development facilitates language learning Genie
Universality of human languages– invariant sequences in development– newborns respond to language– regularity of early production of sounds
55
Nativist theory does not explain:
variance in language skill & fluencey how children understand the meanings of
words why language develops best when there is
another person to communicate with