Child Language Acquisition

Ashish Kulkarni (114056003), Joe Cheri Ross (114050001)

Journey from gaga to water

Introduction

What is Child language acquisition?

"Language acquisition is the process by which humans acquire the

capacity to perceive and comprehend language, as well as to produce and use words to communicate." [1]

"Child language acquisition usually refers to first language acquisition, which studies infants' acquisition of their native language." [1]

What do children already know when they embark on language?

Language acquisition builds on cognitive development [2] [15]

What makes linguistic representation possible?

● Social interaction ● Conceptual representation is common but as they start learning a

language, their paths diverge ● Order of acquisition is affected by the degree of fit between the linguistic

meanings and children’s conceptual representations ● Linguistic encoding of space is shaped by the language around them

● Emergent categories

Tools

CHILDES (Child Language Data Exchange System)

What is CHILDES?

● Database containing data collected from interactions with children in naturally occurring situations. Also contains tools to transcribe and manipulate it. [4]

● CHILDES consists of Codes for Human Analysis of Transcripts(CHAT), Computerized Language Analysis(CLAN) and a database [4]

Database:

● English data: from normal English speaking children

● Non-English data

● Narrative data: from retelling of stories

● Language impairments: from children having language disorders

● Bilingual acquisition data

CHATCHILDES transcription system defines the conventions and rules of data transcription

Ex: ©Begin @Languages: en @Participants: ROS Ross Child BRI Brian Father *ROS: why isn't Mommy coming? %com: Mother usually picks Ross up around 4PM *BRI: don't worry. *BRI: she'll be here soon. *ROS: good. @End

CLAN

Package of analysis programsContains functionalities for Lexical analysis, frequency analysis, lexical field analysis, morphological analysis

CHILDES cont.

CLEXCross linguistic LEXical database [6]

Provides function to● Query vocabulary● Query gestures● Query other actions● Manual cross lexical mappings of words in other languages

CHILD FREQ

● Shows what words children use at what age. [5]

● Database: English part of CHILDES

● Web interface translates query to: search_string: <text>split_sexes: 0 | 1x_axis: “age” | “mlu”age_group: <number>lower_age: <number>upper_age: <number>mlu_group: <number>lower_mlu: <number>upper_mlu: <number>

● http://childfreq.sumsar.net/

Are nouns learned before verbs?

Natural Partitioning vs Linguistic Relativity [3]

Perceptual-Conceptual domain Linguistic domain

concrete concepts like persons, things

predicative concepts of activity, change-of-state, or causal relations

Nominal - proper nouns, common nouns

composite predicate category - verbs, prepositions, adjectives and adverbs

does language follow natural perceptual segmentation of the world?

does our segmentation of the world follow language?

Evaluation 1: Are nouns predominant in early vocabulary?

[3]

Observations

● The pattern of early acquisition of object-reference terms is evident in English

● This is found to generalize well● Similar pattern is observed in production as well as comprehension● Agreement from cross-linguistic vocabulary acquisition - German, Kaluli,

Japanese, Mandarin Chinese, and Turkish

Early acquisition of nouns - Is it due to differences in the conceptual flow (Natural Partitions view)? or - from differences in the stream of language?

Evaluation 2: Is there a relation between initial vocabulary and real-world objects?

Examine the words acquired earliest to decide whether these form-class patterns do in fact correspond to similarities in the kinds of real-world objects referred to

Observations

● Large number of proper nouns (names of individuals)● Large number of names of animate beings, food, and small well-defined

objects● Vehicles, toys, body parts and clothes found in more than one language

although not universal● Predicate terms also although far less represented, show considerable

commonalities● simple change-of-state terms like more, go, down or action followed by

change-of-state terms like spill, eat, and pour

Conclusion -Cognitive categories are indeed the basis for first-word acquisition

Evaluation 3: Is there a possible language based explanation?

Word FrequencyAdults use a large number of nouns, each fairly infrequently, and a small number of verbs, each much more frequentlyThen verbs ought to be acquired before nouns!! Word OrderChildren pay attention to ends of words and sentencesExplains noun preference in English like languages with subject-verb-object order but fails to generalize across languages Morphological transparencySingular-plural noun inflections (dog and dogs) vs tense, person, number and aspect inflections for verbs (kick, kicking, kicked, kicks)Does not generalize across languages - even highly analytical languages (like Japanese, English) show noun predominance

Observation

None of the language-based factors is adequate to explain the noun biasNatural partition hypothesis is the most reasonable view of the early language acquisition - that nouns are learned earlier because their referents are more accessible than those of the predicates But why are certain referents more accessible than others?

Why are object referents more accessible than predicate referents?

● Variability in verb conflation - a language has more degrees of freedom in lexicalizing relations between objects than in lexicalizing the objects themselves

English: The bottle floated into the caveSpanish: La botella entro en la cueva, flotando ● it is not perceiving relations but packaging and lexicalizing them that is

difficult leading to errors - term extensione.g. "You put the pink one to me" (3 years, 4 months, request to be given a pink cup)- surface verb as stative and causative. "The door is open" (stative); "open the door" (causative)e.g. "high me up"- errors in reversals. e.g. "I had to untake the sewing"

How do children learn verbs?

Emergentist Coalition Model (ECM) [2]

conceptualization of events is not problematic; problem lies in word-to-world mapping

● children learn name of action "with result" before learning name of the

"resultless" action○ Ringing a bell produces sound(result)

● children learn names of their own actions first (what we do is more salient)● "Imageability" - running over thinking ● social information● linguistic cues - syntactic bootstrapping

○ Ram gave a book to Hari. Ram transfered money to Hari

Language Acquisition Simulation

DevLex II [8] [9]

Devlex II is able to simulate

● Category formation● Lexical confusion● Effects of Age of Acquisition

Conclusion

● Cognitive development plays a role in language acquisition● Natural partition theory wins over linguistic relativity

Applications ● Helps to analyze linguistic development and mental growth of a child● Define strategies for second language acquisition.

Other Research● Bilingual acquisition research● Study on what is going on in the brain of a child during acquisition

Butterfly video

References

[1] Language Acquisition <http://en.wikipedia.org/wiki/Language_acquisition> [2] Golinkoff, R. M. & Hirsh-Pasek, K. (2008). How toddlers begin to learn verbs. Trends inCognitive Science, 12, 397-403. [3] D. Gentner. 1982. Why nouns are learned before verbs:Linguistic relativity versus natural partitioning. In S. A. Kuczaj, editor, Language development: Vol. 2. Language, thought, and culture, pages 301-334. Erlbaum, Hillsdale, NJ. [4] MacWhinney, B. (1991). The CHILDES project: Tools for analyzing talk. Hillsdale, NJ:Lawrence Erlbaum Associates Inc. [5] Baath, R. (2010). ChildFreq: An Online Tool to Explore Word Frequencies in ChildLanguage. LUCS Minor, 16. Retrieved from http://childfreq.sumsar.net/ [6] Jørgensen, R., Dale, P., Bleses, D., and Fenson, L. (2009). Clex: A cross-linguisticlexical norms database. Journal of child language, pages 1–10. [7] Goodman, J., Dale, P., Li, P. Does frequency count? Parental input and the acquisition of vocabulary 2006 Manuscript under review [8] Zhao, X., & Li, P. (2008). Vocabulary development in English and Chinese: A comparative study with self-organizing neural networks. In B. C.Love, K.McRae & V. M.Sloutsky (Eds.), Proceedings of the 30th Annual Conference of the Cognitive Science Society (pp. 1900–1905). Austin, TX: Cognitive Science Society.

[9] Li, P. 2009. Lexical organization and competition in first and second languages: Computational and neural mechanisms. Cognitive Science 33, no. 4: 62964.[10] Bowerman, M. (1981). The child's expression of meaning: expanding relations among lexicon, syntax, and morphology. In H. Winitz (Ed.), Native Language and Foreign Language Acquisition. New York: New York Academy of Science. Pp. 172-189.[11] Meara, P. (1988). Learning words in an L1 and an L2.Polyglot, 9 (3), D1-E14. [12] Saffran et al., 2001 J.R. Saffran, A. Senghas, J.C. Trueswell The acquisition of language by children Proc. Natl. Acad. Sci. U. S. A., 98 (2001), pp. 12874–12875 [13] Sandhofer CM, Smith LB, Luo J. Counting nouns and verbs in the input: Differential frequencies, different kinds of learning? J Child Language. 2000;27:561–85. [14] Tardif, T. 1996. Nouns are not always learned before verbs: Evidence from Mandarin speaker’s early vocabularies. Development Psychology 32: 492-504 [15] E.V. Clark How language acquisition builds on cognitive development. Trends in Cognitive Sciences, 8 (10) (2004), pp. 472–478 [16] Otto, B. (2006). Language development in early childhood (2nd ed.). Upper Saddle River, NJ: Pearson.

[17] Deb Roy: The birth of a word http://www.ted.com/talks/deb_roy_the_birth_of_a_word.html

[18] CHILDES. http://childes.psy.cmu.edu/

BACKUP

Common ErrorsGiven a 2 part causal event in which one event(X) is bringing about a second event(Y). There are cases where this can be replaced by a simple verb(Z)

ex: make(X) die(Y) :- kill(Z)

Use of 'caused event' predicate as causative verb Eva: Everybody makes me cry Dad: I didn't make you cry Eva: You just cried me

Use of 'causing event' predicate as causative verb Eva: A gorilla captured my fingers. I'll capture his whole head off

Conflating motion and manner I am frowning out the door (move in a frowning manner)

Use of Periphrastic causative instead of Lexical causativeI maked him dead on my tricycle (killed him)

Use of Lexical causative instead of Periphrastic causativeWater bloomed these flowers (made these flowers bloom)

Usage of prefix unHow do I untake this off (take this off)Will you unopen this ? PerspectiveI saw a picture that enjoyed me (that I enjoyed)

Stage

Typical age

Description

Babbling 6-8 months

Repetitive CV patterns

One-word stage(better one-morpheme or one-unit)or holophrastic stage

9-18 months

Single open-class words or word stems

Two-word stage 18-24 months

"mini-sentences" with simple semantic relations

Telegraphic stageor early multiword stage(better multi-morpheme)

24-30 months

"Telegraphic" sentence structures of lexical rather than functional or grammatical morphemes

Later multiword stage

30+ months

Grammatical or functional structures emerge

Rate of vocabulary development

Milestone Nelson 1973(18 children)

Fenson 1993(1,789 children)

10 words 15 months(range 13-19)

13 months(range 8-16)

50 words 20 months(range 14-24)

17 months(range 10-24)

Vocabulary at 24 months 186 words(range 28-436)

310 words(range 41-668)