li2 2008 first language acquisition - university of cambridge 2008 first language...

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First First Language Language AcquisitionAcquisition

– attack imitation/correction and stats theories• Brown findings, fast mapping, goldilocks• constraints on learning: word meaning, null

subjects• crazy rules and chain shifts• abilities in womb• invariant stages• loss of abilities at 12 months• regularisation stage

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TodayToday’’s topicss topics• What does acquiring a language involve?

– Plato’s Problem

• How can we investigate child language given all the inherent difficulties?– sucking, head turn, eye tracking…

• What have these methods shown us about child language?– stages of learning, fast mapping, craziness…

• What do these findings entail for our understanding of language and the mind?– innate knowledge, hypothesis formation…

• How do children manage to learn a language, given such limited and faulty input?

–The Imitation Hypothesis:• Children mimic the speech of their parents

and/or peers. If they are successful, they are reinforced; if they err, they are corrected. Once they have mastered certain forms, they generalize what they have learned to create new utterances, extending what they know by analogy.

C. 427-347 BC

What does acquiring a language involve?What does acquiring a language involve?Plato’s Problem

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Problems with the Imitation HypothesisProblems with the Imitation Hypothesis

C. 427-347 BC

2. We know many things that we were never taught.• word meanings, Principle C…

C. 427-347 BC


3. What children are exposed to is deficient and faulty.– The Gavagai problem– Background noise– Quayle/Bush speech– Parents’ priorities (Roger Brown)

• Child: Momma isn’t a boy, he’s a girl.• Mother: That’s right.• Child: And Walt Disney comes on Tuesday.• Mother: No, he does not.

2. We know many things that we were never taught.

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C. 427-347 BC


Child: Want other one spoon, Daddy.Father: You mean, you want the other spoon.Child: Yes, I want other one spoon, please, Daddy.Father: Can you say “the other spoon”?Child: Other…one…spoon.Father: Say “other”.Child: Other.Father: “Spoon”.Child: Spoon.Father: “Other...Spoon.”Child: Other...spoon. Now give me other one spoon?


3. What children are exposed to is deficient and faulty.

4. What children are taught they often ignore.

C. 427-347 BC




5. Children in all cultures acquire language in the same way.


5-7 months babbling (including deaf children)12-18 months one word stage18 months 2+ word stage; 50 word vocabulary2-3 years fluent sentences7 years ability to acquire language begins to

decline

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C. 427-347 BC





5. Children in all cultures acquire language in the same way.

6. Children create original combinations.

goed = wentallgone outside = I just came inmore page = read me more stories

PlatoPlato’’s Problems Problem

• How do children manage to learn a language, given such limited and faulty input?

–1. The Imitation Hypothesis–– 2. We have a genetic endowment that 2. We have a genetic endowment that

gives us a head start on learning gives us a head start on learning languages.languages.• NB no priors, no learning!

C. 427-347 BC

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• What evidence do we have for UG other than the arguments already adduced?– If there is an innate linguistic component, it should have

an identifiable place in brain.• Damage to this area should impair language, while other

intelligence remains. DYSPHASIAS• Damage to all but this area should produce general

retardation while leaving language intact. TURNER’S AND WILLIAMS SYNDROMES

– Conversely, if language is part of general intelligence, language and other aspects of intelligence should be affected equally in all cases.

Universal GrammarUniversal Grammar

How can we investigate How can we investigate child language given all the child language given all the inherent difficulties?inherent difficulties?

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WugWug teststests

• wug video from Crain lab

Techniques with preTechniques with pre--linguistic infantslinguistic infants

• “In preverbal infants, inferences about categorization have relied on methods based on habituation, conjugate reinforcement, and operant conditioning.”– heart rate (pre-natal)– Multiple Exemplar Habituation/Preferential Looking– Conjugate Reinforcement

• High Amplitude (Non-Nutritive) Sucking• Foot Kicking

– Operant Conditioning• Conditioned Head Turn (Kuhl 1979, 1983)

– 2-alternative anticipatory eye movement response

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Effects of prenatal exposureEffects of prenatal exposure

• Method: measurement of heart rate• Prenatal exposure: mother’s voice (filtered

sound)• Recognition of a prose passage before

birth (DeCasper et al. 1994)• Recognition of the native language (after

birth (Mehler et al. 1986)

HighHigh--Amplitude Sucking (HAS)Amplitude Sucking (HAS)

• [Jusczyk sucking video]

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Conditioned Head TurnConditioned Head Turn• Infant (≥ 0;6) hears

constant background stimulus, e.g. [ba], and target, e.g. [pa]

• Conditioned to turn head only to target set, not background set (correct response reinforced by flashing lights, drumming bears)

drumming bear

• one such test:– [tA] : [ˇA]– [tHA] : [dHA]

0102030405060708090

100

Hindiadults

6-8months

Eng.adults

ta : Tatha : dha

Conditioned Head TurnConditioned Head Turn

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Color vs. shapeColor vs. shapeExperiment: Compare the relative weighting of shape and color in forming visual categories. • Infants trained on either red squares (which

emerged on the left of the occluder) or yellow crosses (which emerged on the right).

• Then tested on red crosses and yellow squares. • Previous studies: color primacy.

Results:• All 5 babies who both generalized and learned

(and did not show a directional bias) showed a preference for color higher than expected by chance.

• They treated red crosses as if they came from the same category as red squares and yellow squares as if they came from the same category as yellow crosses.

• Cf. Baldwin 1989 on form vs color

Two-alternative forced choice; McMurray and Aslin 2004

What have these methods What have these methods shown us about child shown us about child language?language?

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Generalisation by Generalisation by infantsinfants

• Marcus et al 1999– Question

• Do infants extract linguistic generalisations, and in what form?– Method

• 16 infants randomly assigned to one of two groups, each familiarized with 2-minute speech sample– ABA group: 3 reps of each of 16 3-word sentences from ABA grammar (ga ti ga, li na li, etc.)– ABB group: same with ABB grammar (ga ti ti, etc.)

• After habituation, testing on sentences of 3 novel nonce words– test sentences varied as to whether they were consistent or inconsistent with the grammar of the

habituation sentences. – Because none of the test words appeared in the habituation phase, infants could not distinguish

the test sentences based on transitional probabilities, and because the test sentences were the same length and were generated by a computer, the infant could not distinguish them based on statistical properties such as number of syllables or prosody.

– Results• The infants attend longer to sentences with unfamiliar structures.

– Conclusions• “Results suggest that infants can represent, extract, and generalize abstract algebraic

rules.”

0123456789

consistent inconsistent

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Mean time spent looking in the direction of the consistent and inconsistent stimuli in each condition for experiments 1, 2, and 3.

Null subjectsNull subjects• Rate of acquisition

– > 90% of sentences in adult input contain overt subject– Anglophone children don’t master overt sentential subject requirement until as

late as 36 months (Valian 1991) – Compare to acquisition of finite verb placement (before negation and adverbs) in

French by 1;8• Subtleties

– 2-year-olds imitating sentences omitted subjects NPs 19%, object NPs 1%(Gerken 1991)

– Children omit 1st and 2nd persons more frequently than 3rd person arguments (Clancy 1993)

– Children omit subjects of transitives more frequently than subjects of intransitives (Allen & Schroeder 2003, Clancy 2003)

– Children don’t omit:• subjects in questions with a fronted wh-element (Valian 1990)• subjects in subordinate clauses (Valian 1991)

Charlie (2;6)• ah, ___ fell down.• ___ need one toy now deda.• yeah, ___ need help.

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DoubleDouble--WH constructionsWH constructions

• CRAIN VIDEO: What do you think what’s in here?

Acquisition of word meaningAcquisition of word meaning

• Typical stages• Indeterminacy ⇒ error typology• Priors

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Stages of lexical developmentStages of lexical development• Onset around nine months (comprehension) or

12 months (production)• 14,000 words around the age of six

(approximately 10 words per day after the age of two)

• Between six and 17: approximately 3,000 words per year: 50,000 words at the age of 17

• NB saltatory inference of meaning (“fast mapping”, Carey & Bartlett 1978)

Acquisition of lexical meaningAcquisition of lexical meaning

• How do children learn what a word refers to?– Quine’s gavagai problem (“underdetermination”;

subcase of Plato’s Problem)– Cognitive biases

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Semantic errorsSemantic errors• Overextensions (see next slide)

– A word is used for something that has a similar shape, color, or function as the original referent

• daddy = all adult males• ball for moon, dog for bear, donkey, wolf, etc.

– Barrett 1978 (?1996): 7-33% of words– Occurs late in the development of a word (Dromi 1987)– Based on appearance and shape more often than on function

• car for a sled

• Underextensions (see next slide)– A word is used for only a subset of what the word refers to

• shoes for the child's own shoes but not for someone else's shoes– more common early on (Golinkoff et al. 1994)

• Naming errors most common when children are in 50-150 word stage (Gershkoff-Stowe 2001)

OverextensionOverextension

toy dog, soft slippers, picture of old man in furs, all animals

dogwau-wau

piano, phonograph, tunes played on violin, accordion, all music, merry-go-round

rooster crowingkoko

specks of dirt, dust, all small insects, child’s own toes, crumbs, small toad

houseflyfly

extensionsfirst referentchild’s word

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UnderextensionUnderextension

family catmow-mowchild’s dishdishfern in kitchenplantfamily Pontiaccarfirst referent (no extensions)child’s word

Constraining the hypothesis spaceConstraining the hypothesis space

• There literally is an infinity of possible inductive inferences for the child.

• Something must constrain their hypothesis space.– If not, the child cannot learn words for objects.

• Proposal: LAD/UG– “priors” in Bayesian learning

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Semantic priorsSemantic priors• Noun bias• Mutual Exclusivity bias (Markman 1989; cf. Clark 1987 on contrast)

– children assume that the newly introduced word maps to an object which does not yet has a label

• Whole Object bias– children assume that the word refers to the entirety of the referred object, not its

part, material, texture, or color• Object Category bias

– assume that the word is not restricted to the originally referred object, but it can be generalized to other objects of 'like kind'

• Shape bias (Imai, Gentner, & Uchida 1994)– provides children with a basis for determining what objects are ‘alike’ to the

originally labeled object • Form over color bias (Baldwin 1989)

Nouns learned before verbsNouns learned before verbs• Why?

– Ns often refer to individual objects, persons, etc. ∴ their meaning is relatively easy to figure out.

– Verbs are relational, i.e. you can’t imagine what a verb means without the verb's arguments. Therefore, their meaning is relatively difficult to figure out.

• This is not an input effect:– Verbs are more frequent than nouns– Even in 'verb-friendly' languages (e.g., Korean, where verbs

come at the end of utterances, and occur often in isolation) children start with nouns and not with verbs.

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Mutual ExclusivityMutual Exclusivity• Anecdotal evidence: Children say things like That is

not a car it is a taxi. • show child pair of pewter tongs and call it biff, child

interprets biff as tongs in general; when asked for more biffs, it picks out plastic tongs.

• If shown a pewter cup called biff, child assumes it means pewter, not cup, since it already has a word for ‘cup’. When asked for more biffs, the child chooses pewter spoon or pewter tongs.

The whole object biasThe whole object bias• Returning to “look at the dog”:• Which object, exactly, are we talking about?

• The whole dog?• The tail?• The face?• The front-left paw?

• Or are we talking about a property of an identifiable object?– For example, the color of its coat…

• The child assumes that the label refers to the whole object.

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Shape bias and substance biasShape bias and substance bias

• Soja, Carey, and Spelke 1991– When objects are solid (e.g. hammer, pencil), children tend

to categorize them by their shape.– When objects are not solid (hair gel, liquids), children tend to

categorize them by their substance.– Note: in some languages, these distinctions are expressed

in the language (mass nouns vs. count nouns in English), but in other languages, these distinctions are not expressed (e.g., classifier languages, such as Japanese). However, children of both languages respond similarly, which shows that this is not a language effect, but a cognitive effect.

Form over Form over colorcolor

• Baldwin 1989– no label condition: child shown object for

picture book, asked to find another one like it– novel label condition: same, but puppet says

“see this X? Can you find another X?”– 10 trials– 20 2 yr olds, 20 3 yr olds

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What do these findings entail for our What do these findings entail for our understanding of language and the mind?understanding of language and the mind?

• The Language Acquisition Device is constrained by a wide range of priors (syntactic, semantic, phonetic…), which restrict the sorts of linguistic hypotheses entertained by the child.

• Hypothesis formation is rapid and aggressive.– compatible with Bayesian but not

connectionist learning models

ReferencesReferencesAllen, S. & H. Schroeder. 2003. Preferred argument structure in early Inuktitut spontaneous speech data. In J. DuBois, L. Kumpf &

W. Ashby (eds.), Preferred Argument Structure: Grammar as Architecture for Function. Amsterdam: John Benjamins.Barrett, Martyn. 1978. Lexical development and overextension in child language. Journal of Child Language 5:205-219. Bloom, L. 1994. Meaning and expression. In W. Overton and D. Palermo (eds.) The ontogenesis of meaning. Hillsdale, NJ: Erlbaum. Clancy, Patricia. 1993. Preferred argument structure in Korean acquisition. In Proceedings of the 25th Annual Child Language

Research Forum, Eve V. Clark (ed.), 307–314. Stanford, CA: CSLI.Clancy, Patricia. 2003. The lexicon in interaction: Developmental origins of Preferred Argument Structure in Korean. In Preferred

Argument Structure, John Du Bois, Lorraine Kumpf, and William Ashby (eds.), 81–108. Amsterdam: John Benjamins.Crain, Stephen and Mineharu Nakayama. 1987. Structure dependency in grammar formation. Language 63:522-543.Dromi, Esther. 1987. Early lexical development. London: Cambridge University Press.Gerken, L. 1991. The metrical basis for children’s subjectless sentences. Journal of Memory and Language 30.Gershkoff-Stowe, Lisa. 2001. The Course of Children's Naming Errors in Early Word Learning. Journal of Cognition and Development

2.2:131-155.Golinkoff, Roberta, C. Mervis, and K. Hirsh-Pasek. 1994. Early object labels: The case for a developmental lexical principles

framework. Journal of Child Language 21:125-155.Hirsh-Pasek, K., & Roberta Golinkoff. 1991. Language comprehension: A new look at some old themes. In N. Krasnegor, D.

Rumbaugh, M. Studdert-Kennedy, & R. Schiefelbusch (Eds.), Biological and behavioral determinants of language development (pp. 301-320). Hillsdale, NJ: Lawrence Erlbaum Associates.

Markman, Ellen. 1990. Constraints children place on word meanings. Cognitive Science 14:57-77.Markman, Ellen and J. Hutchinson. 1984. Children's sensitivity to constraints on word meaning: Taxonomic vs thematic relations.

Cognitive Psychology 16:1-27.McGregor, K., R. Friedman, R. Reilly, and R. Newman. 2002. Semantic representation and naming in young children. Journal of

Speech, Language, and Hearing Research 45:332-46.Soja, N., Susan Carey and Elizabeth Spelke. 1991. Ontological categories guide young children's indications of word meaning:

Object terms and substance terms. Cognition 38:179-211.

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ReferencesReferencesBaldwin, Dare. 1989. Priorities in Children's Expectations about Object Label Reference: Form over Color. Child Development

60.6:1291-1306.Berko, Jean. 1958. The Child’s Learning of English Morphology. Word 14:150-77.Clark, Eve. 1987. The principle of contrast: a constraint on language acquisition. In B. MacWhinney (ed.), Mechanisms of Language

Acquisition. Hillsdale, NJ: Lawrence Elrbaum. Fagan, J. 1976. Infants’recognition of invariant features of faces. Child Development 47:627-638.Hayne, H. 1996. Categorization in infancy. In C. Rovee-Collier & L. Lipsitt, eds., Advances in infancy research 10:79-120. Norwood,

NJ: Ablex.Hirsh-Pasek K. & Golinkoff, R. M. (1996). The Origins of Grammar: Evidence from Early Language Comprehension. MIT Press.Imai, M., Gentner, D. & Uchida, N. 1994. Children's theories of word meaning: The role of shape similarity in early

acquisition. Cognitive Development, 9, pp.45-75. Jusczyk, Peter & C. Derrah. 1987. Representation of speech sounds by young infants. Developmental Psychology 23:648-654.Kuhl, Patricia. 1983. Perception of auditory equivalence classes for speech in early infancy. Infant Behavior and Development 6:263-

285.Markman, E. 1989. Categorization in children: Problems of induction. Cambridge, MA: MIT Press. McMurray, Bob and Richard Aslin. 2004. Anticipatory Eye Movements Reveal Infants’ Auditory and Visual Categories. Infancy

6.2:203-229.Valian, Virginia. 1990. Null subjects: A problem for parameter setting models of language acquisition. Cognition 35:105-122.Valian, Virginia. 1991. Syntactic subjects in the early speech of American and Italian children. Cognition 40:21-81.Wexler, Kenneth and Rita Manzini. 1987. Parameters and learnability in binding theory. In Thomas Roeper and Edwin Williams

(eds.), Parameter setting, pp. 41-76. Dordrecht: Reidel.

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