Children acquire language through natural interactions with familiar caregivers in everyday contexts. There are three main approaches to collecting and studying child language data: parental diaries, observational studies, and experimental studies. Parental diaries provide rich details but rely on a single observer. Observational studies directly audio record children's speech over time or compare groups. Experimental studies use controlled elicitation methods. Key milestones in early language development include babbling, first words around age 1, two-word combinations by age 2, and rapid growth of vocabulary and grammar thereafter as children pass through predictable stages of morphological and syntactic development.

1. Child language acquisition
KENDALL A. KING
Professor: Dr. Shirazizadeh
presented by: Mojgan Azimi

2. Gathering data on
language acquisition
Naturalness Natural data are similar to the language children use in
everyday life with familiar conversational partners (like the child’s parents)
in familiar contexts (like the home) doing routine activities (like playing).
Representativeness refers to two goals:
A) Language data collected from a particular child should be representative of
the language used by that child every day.
B) The children studied ,should be representative of the general population
under investigation ,for example, Spanish–English bilingual four-year-olds.

3. approaches to collecting child language data
1) Parental diaries detailed descriptions of children’s language development provided by parents.
The most famous diaries belongs to Werner Leopold’s four-volume account of his daughter’s
simultaneous acquisition of German and English.
Advantage
Leopold’s diaries provide rich details and important insights into the process of language
learning in general as well as bilingual language acquisition in particular.
Disadvantage
A diary consists of one observer who is taking notes on just one child, raising the question of
whether his daughter is representative of all children.
The utterances that the child directed at her father were limited and unrepresentative sample.
There are probably errors and omissions in transcription (no audiotapes available).
There is a natural tendency for the parent (or any observer) to selectively focus on out-of-the-
ordinary (and more interesting!) samples rather than on routine and everyday utterances.

4. approaches to collecting child language data
2) Observational studies in the early 1960s, researchers began to audio
record and transcribe the everyday speech of children.
The best-known observational studies belongs to Roger Brown, who
directed a research project at Harvard University which studied the
language of three children from three families.
Brown’s classic book documents the development of grammatical and
morphological systems of three children over time.
This approach allows researchers to examine, for instance, how questions
or past-tense formulations develop over time among different children,
identifying both general patterns and individual differences.

5. Some observational studies have anthropological nature and focus on
language socialization practices and how the patterns of interaction
and parents’ ideologies about language vary cross-culturally.
Observational studies can be conducted in two ways:
A. Longitudinal observe the same participants over several months
or perhaps as long as several years.
B. Cross-sectional record the language behavior of participants
from at least two different groups; for instance, a group of two-
year-old Korean-American children and a similar group of two-
year-old Mexican-American children might be compared in a
cross-sectional study.
approaches to collecting child language data

6. approaches to collecting child language data
3) Experimental studies
In general, experimental studies have narrowly defined
research questions.
They use more controlled methods of collecting data.
Data tend to be elicited through carefully designed techniques
rather than observed and described as they naturally unfold.
They collect less data overall from each participant, but to
have a greater number of participants.

7. High amplitude sucking paradigm (HASP)
Experimental procedures to investigate when and how infants begin to
make sense of the language around them based on infants’ reactions to
stimuli and the fact that they will suck at a higher rate when presented
with novel stimuli.
Using a pacifier attached to a machine, researchers can measure, for
instance, whether the infant perceives a difference between two
similar sounds or two words, such as lice and rice .
This technique measures auditory discrimination.
There are also a number of methods for assessing the production and
comprehension of children’s syntax.

8. The first sounds
Speech perception
The ability to segment the speech stream into
meaningful units, to recognize one’s own
name in the speech stream, or to distinguish
between similar sounding vowels ( /e e/and /
o o/) is a critical skill that infants develop
early in life.
Bootstrap
Bootstrapping refers to the possibility that
skills in one area help the child to develop
competencies in other language areas.

9. During their first few months of life,
infants are able to discriminate between
similar sounds. For example, between /b/
and /p/both in their native language(s) as
well as in other languages.
The first sound made by all infants is
crying. All infants can do this immediately
from birth; although crying may signal
distress, discomfort, boredom, or other
emotions in the first month of life, it is not
an intentional attempt to communicate.
The first sounds

10. The first sounds
Cooing
Coos are vowel-like sounds interpreted as signs of
pleasure and playfulness.
Babbling (4-6 months until 1year)
Characterized by vowel or consonant–vowel
sounds such as ouw-ouw or ma-ma.
Babbling is innate and unconscious, but also
interactive and social.
Around the fifth month, some infants are able
to immediately imitate simple sound sequences
presented to them.

11. The first words
holophrastic stage
Infants tend to use single words to communicate a variety of
complex functions ,ex: mama might be a bid for mother’s
attention or request.
Content words
Refers to words children use which are concrete in their every
day experience (tree, water ,bed) rather than function words (on,
and, the).
Overextension
For example all kind of juice , milk, soda …. are called water.
Under extension
Children might use “baby” only to refer to an infant sibling and
not to the other babies he/she encounters.

12. The first wordsTwo words stage
• Around age two, children use phrases which are not more than two words including
subject and verb (baby cry).
• The ordering of these two-word phrases is not fixed.It is limited to systematic use of
grammatical morphology (for example, the possessive is formed as Miranda bed rather
than Miranda’s bed).
•Children’s capacity for comprehending words outpaces their production ability. For
instance, around the age of one, children can typically understand about seventy
different words, but only productively use about six.
Vocabulary spurt
Around the end of the second year, children’s productive vocabulary begins to develop
rapidly.
multi-word stage
• At approximately two and half years of age, children begin to produce phrases of three
or more words (Daddy cook dinner ).
• Children language at this stage is called telegraphic speech. It is direct and makes only
limited use of morphological and syntactic markers.

13. First sentences: morphological
and syntactic development
Children’s regular use of grammatical forms (even “incorrect”
usages such as broked or foots) may reflect children’s developing
grammatical rule systems.
At very young ages children are tuned into the semantic
significance of their language’s grammatical structures.
All children follow similar patterns and pass through the same
developmental sequences as their competence develops.
The development of inflectional and derivational morphology in
children’s productive language becomes apparent once the child
enters the multiple-word stage and continues through age five.

14. First sentences: morphological and
syntactic development
Mean length of utterance (MLU)
• MLU is a measurement of the complexity of children’s language and is calculated
from the average number of morphemes (not words) per utterance.
• Brown through analysis of 3 children’s spontaneous speech illustrated that:
1. The order of acquisition was similar (with present progressive, plural, and past
irregular verb forms appearing first) .
2. The age at which children acquired competence in using these forms varied widely .
3. The MLU stage served as a good index of the level of development for grammatical
morphology .

15. Jean Berko’s famous “wug” study
• Berko asked young children of different ages to form the
plural of unknown, non-sense creatures, such as “wugs".
• Berko found that even preschool children who were able
to form the plural and could apply this rule correctly in
novel contexts, were not just repeating forms which
they had previously heard.
• In developing these rules, children pass through
predictable stages.
• Children overgeneralize in the early phases of
acquisition, they apply the regular rules of grammar to
irregular nouns and verbs.
• Overgeneralization leads to forms like goed, eated,
foots, and fishes.

16. 3 phases of overgeneralization
1. The child uses the correct past tense of go, for instance, but does not relate this
past tense went to present-tense go. Rather, went is treated as a separate
lexical item.
2. The child constructs a rule for forming the past tense and begins to
overgeneralize this rule to irregular forms such as go (resulting in forms such as
goed).
3. The child learns that there are (many) exceptions to this rule and acquires the
ability to apply this rule selectively.
This development is “U-shaped” that is, children can appear to be decreasing rather
than increasing in their accuracy of past-tense use as they enter phase 2. However,
this apparent “back-sliding” is an important sign of linguistic development.

17. developmental sequences
•Negation and interrogative development are
interrelated and also dependent upon development of
the necessary vocabulary. (auxiliaries: do, does, did, is,
am, have, has)and (modals : can, could, may, might) .
•Children’s language production has a rule-governed
nature.
•Mistakes reflect the developing rule system of
children’s language.

18. Cross-linguistic and cross-cultural aspects
of language acquisition
Speakers of different languages use the same basic mental
mechanisms (for instance, working memory or perceptual
processing) but may use them differently depending on the
language being spoken.
• Lexical and grammatical development
Onset times appear very similar across languages for both word comprehension
(eight to ten months) and word production (eleven to thirteen months)
Wide individual variation exists within each language concerning the pace and size
of vocabulary growth (for example, at two years, children’s productive vocabularies
range from 1 to 500 items).

19. Cross-linguistic and cross-cultural aspects
of language acquisition
• The emergence of nouns and verbs
It was long believed that nouns were the first words to appear in
children’s speech, but verbs are among the first items acquired by Korean
children.
• Development of grammatical competence
Across the world, young children use grammatical competence to convey
similar intents: (possession, location, and volition).Nevertheless, there
are important differences in the linguistic forms .These differences
reflect the nature of the language being acquired by the young child .

20. Cultural differences
Children are born into distinct communicative
systems around the world . These systems
potentially stress different aspects of child-
rearing and hold different ideologies concerning
language use and what it means to be a “good”
child, often resulting in different interactional
patterns with and around the infant .

21. Bilingualism
•It refers to the number of languages acquired by a child.
•Up until the 1960s, most psychological research were on the belief
that bilingualism resulted in lower intelligence and diminished
cognitive abilities.
•This paradigm shifted dramatically with Peal and Lambert’s (1962)
research among French–English bilinguals in Montreal, Canada.
•Their research proved that bilinguals have greater metalinguistic
awareness (knowledge and awareness about language as a system)
and mental flexibility, as well as the ability to think more abstractly.

22. Bilingualism phases
Code-mixing
All bilingual children go through a period of code-mixing, that is,
they move back and forth between their two languages, seemingly
without discrimination .It reflects children’s developing grammar
and lexical system and the lack of differentiation between the two
languages .It might also be the result of a child’s limited vocabulary.
Code-switching
It consists of intentional use of more than one language for
symbolic, strategic, or communicative purposes by bilinguals.

23. Bilingualism controversial
researches
• Unitary system hypothesis refers to whether a bilingual child begin with
just one grammar and lexical system that later becomes differentiated as
the child learns to distinguish between the two languages.
• Separate systems hypothesis refers to whether a bilingual child have
two grammatical and lexical systems from the outset.
• The result shows that the amount of exposure to each language directly
contributes to competency levels. There are in fact relatively few balanced
bilinguals, or individuals who have identical and native competence in all
areas of both languages.

24. Behaviorism
• A theory that held that language is
essentially a habit, a behavior like any
other, which is mastered through
general learning principles. (imitation,
reinforcement, and punishment).
• Behaviorists tend to focus on
observable behaviors rather than
internal or innate processes.
• While this approach has a certain
commonsense appeal, behaviorism is no
longer the dominant research paradigm
in the study of child language.

25. Nativism
In contrast to behaviorists, nativists hold that language is an innate capacity.
This special capacity is limited to humans and differs from any type of animal
communication.
In contrast to adults, children reach near mastery of their native tongue in just a
few short years, without instruction or any apparent effort.
Poverty of stimulus The point that input alone is inadequate to support children’s
language learning has been referred to as the poverty-of-the-stimulus
argument.
Children rarely receive specific feedback, on the grammaticality of their
utterances, as adults typically focus on the content of a child’s utterance rather
than its linguistic accuracy.
Nativists assert that children create or generate a rule-based system.

26. language acquisition device ,LAD
• According to nativists ,language is claimed to be a species-
specific or uniquely human cognitive capacity which is the
result of an innate language acquisition device.Although
the location and content of the LAD remains a topic of
debate .
• LAD is supposedly what allows children to attend to
language and develop an appropriate grammar quickly,
without effort, and with no specialized input.

27. critical or sensitive period
There is a time limit, also known as a
critical or sensitive period, that
learning takes place, and after this
period (typically around puberty),
complete acquisition of a first or second
language becomes difficult.

28. Connectionism
• Connectionists challenge nativists and contend that general learning
mechanisms such as sensitivity to distributional patterns in the input are
sufficient for at least some aspects of language acquisition, including syntax.
• This approach, also variously known as the “information processing
approach” or a parallel distributed processing (PDP) approach, generally
holds that processing is carried out by nodes (roughly analogous to neurons)
that are connected to other nodes in a network by pathways that vary in
their strength.
• Connectionists argue that children can learn the regularities of the language
through an inductive process based on exposure to many examples.

29. Social interactionism
• Social interactionists point to the importance of child–caregiver interactions in the
language acquisition process.
• They stress the role of the LASS (language acquisition support system) in explaining
child language acquisition.
• They believe that ,the daily contacts and emotional bonds a child has with his/her
caregivers are important parts of the LASS.
• Interacting with children, caregivers tend to use a special form of speech – including
short, simple sentences with higher pitch and exaggerated intonation, as well as
sentences focused on the objects and events in the child’s immediate environment or
increased use of diminutives (e.g. doggie or kittie), as well as repetition and imitation.
• This language is called child-directed speech or CDS.They are also known as motherese or
baby talk.

30. Social interactionism
• Caregivers of young children may also use recast to help the child
master more complex language forms.It attracts the child’s attention to
problematic forms and to actively involve him/her in the conversation.
• Through these interactions and ritualized patterns of language use
(such as peekaboo and Where’s baby?), children gradually learn about
turn-taking and become aware of the communicative nature of
language
• The caregiver supports, or scaffolds, the child’s emerging linguistic
system.

31. “Nature versus Nurture”
• Naturists are stressing the
importance of biological and
genetic programming (the
nativist) .
• Nurturists are pointing to the
role of the environment
(behaviorist).
• While there is growing
agreement that both nature and
nurture are critical, scientists
disagree on the relative
importance of each.

32. Thank You