Language Development
Some definitions
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Language - a socially shared code or
conventional system for representing
concepts through use of arbitrary symbols
and the rule governed combinations of those
symbols
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Speech - a verbal means of communicating or
conveying meaning
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Gestural precursors to speech – and gestural forms
of speech
Questions 1
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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?
Topics
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Crying
Pre-linguistic speech
First word acquisition
The vocabulary spurt
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Crying
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Earliest vocalization –Curvilinear development
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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
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Then recruited for communication
Continuum of intentionality
Both directed and undirected crying still present at 12
months
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Two crying functions
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“[N]aturally occurring cry in 26 infants
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By 12 mo, most infants sometimes directed their
crying toward the caregiver and elaborated the
sounds by the use of gestures.
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(aged 2.8-13.2 mo) and their mothers at home.
But most continued to exhibit simple, undirected
crying.
Crying is both intentional and not intentional
Shows increasing variability and sophistication in
form and function.
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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
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Different acoustic patterns
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Basic hunger cry
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Pain cry
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rhythmic pattern of loud crying, silence, inhalation
loud, long shrill cry, then breath-holding silence
Fake cry
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low pitch and intensity, poorly articulated moans
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Crying judgments
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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
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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.
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Gustafson, G. E.; Green, J. A. ‘Acoustic features of cry perception:
Infant development. ’Child Development. 1989 Aug Vol 60(4)
772-780
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Prelinguistic speech
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Use of sounds in a communicative manner
before speech (no words or grammar)
Progress through stages culminating in
speech-like vocalizations
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Phonation, Gooing, Expansion, Canonical
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Some overlap in vocalizations characteristic of stages
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Kim Oller
Phonation Stage, 0-2/3 months
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Vowel-like (“quasi-resonant”)
Produced with normal speech like phonation
involving vibration of the larynx but with the
vocal tract at rest
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“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
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Still vowel-like
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more guttural & throaty
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/e/ & /u/
but last longer
produced in the back of the vocal cavity
thought to be precursors to consonants
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/k/ /g/
Expansion Stage, 3 - 8 months
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Isolated vowel-like sounds
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Usually produced with the mouth open
Full vowels (“fully resonant nuclei”)
Vocal repertoire expands dramatically
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Infant experiments with sound production, varying pitch,
volume, & rate
Intentional communicative play
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Already beyond pre-set animal calls
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Which have set form and set causes
Infant vocalizes for pleasure (just to have fun) or
displeasure
Checking out the new sound system
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Yells/whispers: playing with amplitude/intensity
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Squeals & Growls: playing with pitch
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squeals = high pitch, growls = low pitch
Raspberries
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labial trill & vibrants
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yells = high intensity, whispers = low intensity
Cannot transcribe as adult syllables
Marginal babbles
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consonant-vowel (CV) sequences
the transition between C & V is slow and drawn out
immature syllables
Oller, K.
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Functional flexibility of infant
vocalization. Oller, et al. 2013. PNAS
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‘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.
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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.’
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‘Functional flexibility is a sine
qua non in spoken language
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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.’
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Canonical Babbling Stage, 6-10 mos
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CV sequences
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Transition between CV are crisp
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/ma/ /da/ /ada/
Sounds like natural syllables in parent’s language
Parents good at identifying this stage
Reduplicated babbling
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/baba/ /dadada/ /mama/
Importance of Babbling
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Involves increasing control over the articulatory
mechanism
Important pre-speech developmental milestone
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Should be present by 10 months!
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Occurs in Down Syndrome, premature, low SES kids and in all
cultures
But its delayed in hearing impaired infants and deaf children
Limitations of Babbling
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At end of stage, infants begin to use patterns or
rising intonation that resemble adult speech
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also known as gibberish, jargon, or conversational
babbling
It has intonation contours of language being learned
Infants learn the music before the words
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Does not refer (to objects, people, etc.)
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Is not language
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Integrative stage (9-18 months)
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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
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sounds like the child is having a conversation
but you can’t understand what they are saying
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First word definitions
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Function
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They are first words because they refer
Arbitrary sound is paired with an object
Often but not always nouns in the environment
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First Word Characteristics
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Form
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Conventional
Typically brief
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1 syllable, e.g., ‘no’
or a reduplicated syllable, e.g., ‘ma-ma’
Most linguistically common words
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May be developed by babies
And may be the easiest to articulate
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First Word Timetable
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Appear
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Typically: 11 to 13 months
Normal range: 10 to 14 months
Normal variation
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13 month vocabularies: 0 - 45 words
Should have first word by 15 months
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Screen for delay
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First 50 words
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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
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Cross-cultural differences in first
words acquired
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How words are learned
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Reference: Pairing of object names with objects
Child must visually attend while label is provided
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So receptive joint attention helps
Helps if parent labels what child is already looking at
May be facilitated by routines
Metalinguistic insights
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“Things have names” “I can make things happen with
words”
Corresponds to vocabulary spurt
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Rapid, accelerating growth
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Nouns
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Most common throughout language
development
Why do infants learn nouns most rapidly?
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Adults tend to label objects more than they
label actions (fly, run) or describe objects
(yellow crayon)
Verbs are conceptually more complex;
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nouns are concrete where verbs tend to be more
abstract
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Vocabulary Growth
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Slow at first
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18 month infant
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can take 3 or 4 months after first words to
achieve a vocabulary or 10 to 30 words
typically has a vocabulary of 50 words
18 - 22 months
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Vocabulary spurt
From 50 to 300 words in few months
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Meta-linguistic insights
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Things have names” Corresponds to
vocabulary spurt
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Rapid, accelerating growth
“I can make things happen with words”
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Effort to express/understand participate
Intentionality model (Bloom)
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Language learning is effortful
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Receptive and Expressive
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2 types of vocabulary development
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Receptive - understands others’ words
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Say ‘bye-bye’. ‘Where’s Daddy?’
13 months - 50 words
Expressive - total words used (productive)
Receptive typically outpaces expressive
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Child understands more words than they use
Individual Differences
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2 styles of language
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Referential style - use language primarily to
label objects in their environment
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Expressive style - use language as a means for
engaging in social interaction
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E.g., dada, doggy, baba
Hi, bye, ut-oh
More kids have an expressive style although
most have a combination
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Syntax = grammar
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Evidence of syntax
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Nonrandom combinations
Development of syntax
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Takes place with no explicit instruction.
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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?
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Syntax of one word speech
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Holophrase - a single word used to express
complex meanings
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“Cookie” = “Give me the cookie”
Early utterances are telegraphic
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The essential words are used to convey whole ideas
Syntax of 2 word sentences
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Emerge
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15 – 24 months, mean is 18
Usually have 50 words in vocabulary before
combining words
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7 months after their first words
First sentences typically consist of nouns, verbs &
adjectives
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Uses: name, locate, negate, question, etc.
Pivot word
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frequently occurring word attached to a variety of other words
More: Mommy, milk, hug
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Common Errors
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Underextension
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Overextension
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Word refers to particular exemplar
“Car” = family’s car
Word refers to inappropriately large class
“Car” refers to all big things with wheels
Interplay between two yields correct word
usage
Measuring grammatical
development
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Mean length of utterance (MLU) is a measure of
syntactic development.
Average length of the child’s utterances is
calculated in morphemes - NOT WORDS
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a morpheme is the smallest unit of meaning in a word
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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)
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MLU length
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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
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Comprehension: Gogate
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Comprehension: Gogate
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Motherese/child directed speech
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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
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cultural differences stem from mother’s styles of
interactions and child rearing beliefs
Has positive affect on early language development
Infant directed speech
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Slower rate, higher pitch, longer pauses
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Brief, grammatically correct sentences
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Use of simple syntax
Key words at end & are spoken in a higher &
louder voice
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Repetitive & reduplicated
Diminutive used
https://www.youtub
e.com/watch?v=cSC
– Objects may be over described XMfeo74Q
Vocabulary is concrete
Children’s early comprehension
of syntax
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Assessment methods involving action such as
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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.
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The preferential looking
paradigm
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Has helped clear things up.
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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
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Child hears
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“Cookie Monster is tickling Big Bird”
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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.
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Statistical learning
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Statistical
rules 
Learning
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How Is Language Learned?
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Theories of language development
Learning Theory
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Language is learned through experience. Emphasis
on role of child’s environment
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Reinforcement ~ Parents reinforce or reward infants
babbles that are approximations of real words (B.F.
Skinner).
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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)
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Learning theory cannot explain:
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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
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Nativist Theory
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Innate factors cause children to attend to &
acquire language
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Chomsky’s psycholinguistic theory
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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:
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Verbal function is localized in speech centers
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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
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neural development facilitates language learning
Genie
Universality of human languages
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invariant sequences in development
newborns respond to language
regularity of early production of sounds
Nativist theory does not explain:
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variance in language skill & fluencey
how children understand the meanings of
words
why language develops best when there is
another person to communicate with
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Review Syllabus
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