Child Language Acquisition

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Child Language Acquisition

• Sahil Thapa
• Amit Kumar Upadhyay
• Prakhar Goyal
• Naineet Patel

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Language Acquisition

• Ponder on Language Acquisition
• A complex task
• Encompasses research fields
• Natural Language Processing
• Neural networks
• Psychology
• Statistics and other related fields

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Language Acquisition- The meaning..

• Language acquisition - process by which the
  language capability develops in a human.
• First language acquisition or Child Language
  Acquisition concerns the development of language
  in children.
• da --gt daddy --gt daddy loves me ..

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Why to learn that !!

• Long range influences on adult behaviour as the
  twig is bent, so grows the tree !!
• Children change so rapidly compared to us adults.
  
• Insights into complex adult processes.
• Interesting subject matter.

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Lets learn How Krish learns to talk

• 1 Week "WAAAAAAAA!"
• Translation - "I'm hungry!"
• Krish learns that people pay attention to you
  when you make noises

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Lets learn How Krish learns to talk

• 6 Months "Babadadagugubaba"
• Translation - none.
• Krish has learned that making noises is fun.

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Lets learn How Krish learns to talk

• 1 Year "paalle - g"
• Translation "I want biscuit" (First time he ate
  Parle G biscuit, although this time, it is a
  different biscuit now)
• Krish has learned that you don't always have to
  point to show people things.
• You can correlate one type of thing to its
  similar type.

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Lets learn How Krish learns to talk

• 2-3 Years "Chacha Choudhry hit boy. Stick daddy.
  No Talks !!"
• Translation Chacha Choudhry hitting boy with
  his stick. And stop reading this story daddy! (
  Because I'm scared)
• He has learned that language helps you be quite
  specific about what you feel and what you want.

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Lets learn How Krish learns to talk

• 5 Years "Papa, mai yeh kaam karna chahta huun!"
• Finally he has learned the core structure and
  grammar of the language.
• By now, he is almost able to communicate with his
  fellow people and from now onwards he will try
  expanding the vocabulary and knowledge of the
  language.

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Outline

• Motivation Meaning
• Some facts about language acquisition
• Theories explaining Child Language Acquisition
• Imp Stages in CLA
• CHILDES

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3 imp facts about CLA

• 1. REGARDLESS OF THE LANGUAGE KIDS ARE
  EXPOSED TO....
• at 6 weeks they coo
• at 6 months they babble
• at 1 year they produce their first word
• at 2 years they construct 2 word sentences
• at 5 years they have almost acquired the core
  grammar of their language

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3 imp facts about CLA

• 2. Universal phenomenon phonologically,
  syntactically, and semantically.
• 3 . A natural process
• Their syntax is very rarely explicitly corrected,
  and attempts at such correction are almost
  invariably unsuccessful.

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Outline

• Motivation Meaning
• Some facts about language acquisition
• Theories explaining Child Language Acquisition
• Imp Stages in CLA
• CHILDES

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Theories of Language Acquisition
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Chomskys Universal Grammar Theory

• Language is a process of free creation its laws
  and principles are fixed, but the manner in which
  the principles of generation are used is free and
  infinitely varied. Even the interpretation and
  use of words involves a process of free creation
• -- Avram Noam Chomsky

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Chomskys Universal Grammar Theory

• Language acquisition is influenced by language,
  not controlled by it !!!
• Arguments
• Language is complicated
• No formal instruction.
• Always succeed and that too in a short period of
  time
• Independent of other mental tasks.
• Use deduction rather than by imitation or
  memorization.

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Chomskys Universal Grammar Theory

• Neurological system in human brains that supports
  language acquisition. Language Acquisition
  Device or LAD.
• Children are exposed to infinite data and given
  data LAD produce a finite set of grammar rules.

Data as Input
Grammar Output
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Chomskys Universal Grammar Theory

• Children learn language by applying this
  unconscious universal grammar to the sounds they
  hear.
• Universal grammar forms the foundation of all
  human language. A universal grammar can be
  equated with computer languages. There are many
  kinds of computer languages, but they all have
  some fundamental similarities

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Chomskys Universal Grammar Theory
Lexicon
Base Rules
Transformation Rules
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Chomskys Universal Grammar Theory

• Transformation rules are language specific..
• Single Deep Structure can be expressed in many
  different Surface Structures
• Ambiguity in the sentence
• I have seen eating a rabbit Deep Structure
• I have seen someone eating a rabbit..
• I have seen a rabbit eating something.
  

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Chomskys Universal Grammar Theory

• So how these transformation rules look like?
• Subject-auxiliary inversion (SAI).
• X NP AUX Y gt X AUX NP Y
• Ram is eating an alphonso mango."
• Is ram eating an alphonso mango?".
• the bird was killed by the cat ? the bird was
  killed. Deletion ABC ? A B
• Get out! ? Get out of here!
• addition/insertion, AB? AB C
• Mary up ? Call up Mary
• permutation ABC? ACB Call

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Theories of Language Acquisition(Revisiting..)
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The Cognitive Approach (Piaget)

• Children can only use certain linguistic
  structures when they understand fully the
  concepts surrounding them
• A child can not use comparison of size if
  he/she does not understand
• the concept of size. Can focus on only
  one aspect or dimension
• of problems.
• Example - row of 5 blocks and a row of
  7 blocks can count the blocks
• in each row and can tell number
  contained in each. But cant tell which
• is longer?
• Progressive reorganization resulting from
  maturation and experience.
• Based on discrepancies between what they already
  know and what they discover, they modify it.

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The Cognitive Approach (Piaget)

• Sensorimotor stage (0-2 yrs)
• Trial and error learning.
• Behaviors become goal directed.
• Object permanence.
• Preoperational stage (2-7 yrs) mentally
  represent objects and events.
• egocentric thoughts and communications.
• unable to focus on more than one concepts
  simultaneously.

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The Cognitive Approach (Piaget)

• Concrete operational stage(7-11yrs)
• Abilities of conversation and reversibility.
• Organized and rational thinking.
• can solve problems with more logical fashion.
• Formal operational stage(11 yrs)
• More abstract thinking.
• Higher order reasoning.
• Can combine and classify in more
  sophisticated way.

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The Cognitive Approach (Vygotsky)

• Knowledge from external world transformed and
  internalized.
• Not isolated 'lone thinker', culture and society
  are more important for a child's thought.
• Social Interaction and then cognition
• Development first on a social plane. Learn from
  parents' behavior, their speech, imitate them.
  Parents correct them.
• Afterwards information becomes internalized.
• Language is now inner speech.

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The Behaviorist Approach (Skinner)

• language is acquired by conditioning and
  reinforcement
• Learns through rewards and punishments.
• Children learn to speak by
  imitation. Parents then reinforce or correct
  their speech. Children dont imitate perfectly
  they may say words similar to what they hear
  around them.
• Problems
• 1. They over-extend language patterns they
  already know
• Steal gt stealed gt instead of stole
•   Drive gt drived gt instead of drove
• This is not
  imitation instead it is an extension
• as adults do
• Poverty of the Stimulus

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Outline

• Motivation Meaning
• Some facts about language acquisition
• Theories explaining Child Language Acquisition
• Imp Stages in CLA
• CHILDES

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Significant stages in Child Language Acquisition
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Significant stages in Child Language Acquisition
Stage - 1
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Significant stages in Child Language Acquisition
Stage - 2
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Significant stages in Child Language Acquisition
Stage - 3
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Significant stages in Child Language Acquisition
Stage - 4
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Significant stages in Child Language Acquisition
Stage - 5
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Significant stages in Child Language Acquisition

• This model explains the process of language
  acquisition.
• Variations possible among children at each stage
  but little variation in sequence of language
  learning.
• From stage-5 on, what is learned increasingly
  depends upon experience and environment
• Opportunities to use language
• And hearing it used.
• Involves wide range of contexts and corresponding
  environment.

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Outline

• Motivation Meaning
• Some facts about language acquisition
• Theories explaining Child Language Acquisition
• Imp Stages in CLA
• CHILDES

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CHILDES
CHIld Language Data Exchange System
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Childes Its relevance !!

• A system for transcribing and encoding childrens
  interactions.
• It is developed at CMU.
• It helps in studying syntactic construct and Part
  of Speech.
• Research on various language disorders.

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A brief introduction

• Founded 1984
• Director Brian Mac Whinney
• An international Database for the study of first
  and second language acquisition
• Tools to analysis conversational interaction
• Linking data to digitized audio and video
• 4500 Members
• 1500 published articles

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Components

• CHILDES includes three integrated components
• CHAT
• the system for discourse notation and coding
• CLAN (Child Language Analysis)
• the set of computer programs for searching and
  manipulating the database
• Database
• language community from over sixty major projects
  in English and additional data from various other
  languages

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An Example

• A picture description task
• - the patient is mentioning animal in a set of
  pictures
• - each picture having animal eating bananas.
• - only single animal appears in each
• - raw form, the patient said was simply,
• rabbits, squirrel and monkeys
• Here is how this is transcribed

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Transcription

• _at_g 3a bunny is eating banana
• PAT rabbits .
• mor DET0 Nrabbit-PL
• err rabbits rabbit SUB
• _at_g 3b squirrel eating banana
• PAT squirrel.
• mor DET0 Nsquirrel
• _at_g 3c monkey eating banana
• PAT monkeys .
• mor DET0 Nmonkey-PL.
• err monkeys monkey SUB

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References

• Manolson, Ayala  It Takes Two to Talk, A Parent's
  Guide to Helping Children Communicate.  1992
• Communication and Cognition - Artificial
  Intelligence, Vol. 12, Nos. 1-2, pp. 45-61,
  Special Issue Self-Reference in Biological and
  Cognitive Systems, Luis Rocha
• On the role of parameters in Universal Grammar a
  reply to Newmeyer, Ian Roberts and Anders
  Holmberg, University of Cambridge/ University of
  Newcastle upon Tyne
• A Working Paper on First Language Acquisition
  Research Some Notes on Theory and Method,
  Joseph Galasso, San Diego State University (1999)
• The CHILDES System, Brain Mac Whinney, From
  American Journal of Speech-Language
  Pathology,Vol.5,1996, Page 5-14

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• Thank You