Child Language Acquisition

Sahil Thapa Amit Kumar Upadhyay Prakhar Goyal Naineet Patel Child Language Acquisition

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

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 --> daddy --> daddy loves me ..

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.

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

Lets learn How Krish learns to talk • 6 Months "Babadadagugubaba" • Translation - none. • Krish has learned that making noises is fun.

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.

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.

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.

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

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

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.

Theories of Language Acquisition

Chomsky’s 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

Chomsky’s 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.

Chomsky’s 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. DataasInput GrammarOutput

Chomsky’s 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

Chomsky’s Universal Grammar Theory Lexicon BaseRules Transformation Rules

Chomsky’s 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.

Chomsky’s Universal Grammar Theory • So how these transformation rules look like? • Subject-auxiliary inversion (SAI). X NP AUX Y ==> 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” A+B+C → A+ B: • ‘Get out!  Get out of here!; “addition”/”insertion”, A+B→ A+B+ C: • Mary up  Call up Mary “permutation” A+B+C→ A+C+B Call

Theories of Language Acquisition(Revisiting..)

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 can’t 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.

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.

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.

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.

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 don’t imitate perfectly they may say words similar to what they hear around them. • Problems : • 1. They over-extend language patterns they already know; Steal > stealed > instead of stole Drive > drived > instead of drove This is not imitation instead it is an extension as adults do • Poverty of the Stimulus

Significant stages in Child Language Acquisition

Significant stages in Child Language Acquisition Stage - 1

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.

CHILDES CHIld Language Data Exchange System

Childes – Its relevance !! • A system for transcribing and encoding children’s interactions. • It is developed at CMU. • It helps in studying syntactic construct and Part of Speech. • Research on various language disorders.

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

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

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:

Transcription • @g: 3a = bunny is eating banana • *PAT: rabbits [*]. • %mor: DET|0 N|rabbit-*PL • %err: rabbits = rabbit $SUB; • @g: 3b = squirrel eating banana • *PAT: squirrel. • %mor: DET|0 N|squirrel • @g: 3c = monkey eating banana • *PAT: monkeys [*]. • %mor: DET|0 N|monkey-*PL. • %err: monkeys = monkey $SUB ;

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 IssueSelf-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

Thank You

Child Language Acquisition