LING 101 Lecture outline M Apr 9 Today s topics: Child language acquisition Methods in acquisition research Background reading CL Ch 9, 1, The study of language acquisition CL Ch 9, 6, What makes lg acq possible? 1
0. Course information HW #8 is due - Please put it in the pile on the table in the front that is labeled with your TA s name and recitation number Myke (10:10) 601 Melissa (11:15) 602 Mika (11:15) 603 2
1. Main ideas: Child language acquisition Adults can speak and understand their native language(s) because they have a mental grammar of that language: - a lexicon, where sounds, meaning, and other unpredictable information are stored for each morpheme - rules of their mental grammar, including morphological, phonological, and syntactic rules and principles 3
1. Main ideas: Child language acquisition Adults can speak and understand their native language(s) because they have a mental grammar of that language: - a lexicon, where sounds, meaning, and other unpredictable information are stored for each morpheme - rules of their mental grammar, including morphological, phonological, and syntactic rules and principles 4
1. Main ideas: Child language acquisition Any (normally developing) infant has the potential to develop the mental grammar of any language - Infants all start out with their mental grammar at the same (universal) original/default settings: Universal Grammar - When infants are exposed to language data, they will begin to develop the mental grammar needed to produce and comprehend a particular adult language (the target language) We can analyze a child s mental grammar with the same tools we use for adult languages 5
1. Main ideas: Child language acquisition A child who has not fully acquired a target adult language still shows evidence of having a mental grammar only, not (yet) the same mental grammar as that of the target language Studying the process of language acquisition can give us important insight into: - the nature of the mental grammar for a particular language - the range of the characteristics of possible human mental grammars: Are there mistakes that children never make? 6
1. Main ideas: Child language acquisition Learning a native language is not the same as learning to do math or ride a bike - This is why the term acquisition, not learning, is typically used for this process Children do not acquire language because their parents teach it to them Children acquire language through contact between the language data in the environment and the (universal) acquisition mechanism of the mental grammar 7
1. Main ideas: Child language acquisition We will now consider: What role do the following types of parent/child interaction play in the child s language development? - Imitation - Feedback / correction by adults - Caregiver speech ( motherese ) - General cognitive development 8
2. Acquisition is not just imitation Some people assume that children simply learn language by imitating adult speakers - Sometimes a child can imitate more accurately than they generally speak However, imitation is far from the only process involved in language acquisition - What characteristics of language are incompatible with the imitation hypothesis? - What often happens when a child is explicitly encouraged to imitate? 9
2. Acquisition is not just imitation What characteristics of language are incompatible with the imitation hypothesis? - Creativity/productivity of language - Morphological overgeneralization and other child-specific linguistic rules goed, bringed What would the child be imitating? 10
2. Acquisition is not just imitation What often happens when a child is explicitly encouraged to imitate? (CL, pp 378-379) Child: Father: Child: Father: Child: Father: Child: Father: Child: Father: Child: Want other one spoon, Daddy. You mean, you want the other spoon. Yes, I want other one spoon, please Daddy. Can you say the other spoon? other...one...spoon. Say other. other. spoon. spoon. other spoon. other...spoon. Now give me other one spoon? 11
2. Acquisition is not just imitation What often happens when a child is explicitly encouraged to imitate? - The child often continues to follow the rules of his/her own mental grammar, even when it makes the imitation imperfect 12
3. Acquisition is not just via feedback Some people assume that parents teach language to children by correcting their errors But when parents correct their children, it s more likely to be about the truth of their utterances than phonology/morphology/syntax Child: Mama isn t boy; he s a girl! Parent: That s right. Children often ignore (or, their mental grammars have difficulty interpreting) parental feedback see point above about imitation 13
3. Acquisition is not just via feedback Recasts (repeating with readjustment): Do they always serve as a cue for non-adult-like utterances? Child: Boy chasing dog. Parent: Yes, the boy is chasing the dog. Child: The dog is barking. Parent: Yes, the dog is barking at the kitty. 14
3. Acquisition is not just via feedback Is there a link between recasts and acquisition? Two experiments: - No? Recasts had no effect in a study of the acquisition of determiners a, the - Yes? A single recast was often enough to permit learning the irregular past tense of a novel (made-up) verb Is there a principled difference between these two examples of recasts that might explain the different results? 15
4. A role for caregiver speech? In many (not all!) cultures, adults use a special speech style with young children, known as caregiver speech (also called infant/childdirected speech, motherese ) Some characteristics of caregiver speech by middle-class English-speaking caregivers (see Table 9.22 on p 377 of CL for more) - slower speech - tendency to refer to the here and now How might these aspects of caregiver speech be helpful in acquisition? 16
4. A role for caregiver speech? How might these aspects of caregiver speech be helpful in acquisition? - Slower speech might help with phonological acquisition - Tendency toward reference to the here and now may help with semantic acquisition But, many features of caregiver speech do not seem to affect acquisition - Example: Relative frequency of grammatical morphemes (inflectional affixes and function words) does not predict acquisition order 17
5. A role for general cognitive development? Some possible correlations between language development, general cognitive development - Object permanence Burst in vocabulary development But: Evidence that language and cognitive development are at least partly independent - Language can be intact while cognition is impaired - Cognitive function can be normal while mental grammar is impaired 18
6. Methods in acquisition research Naturalistic approach - Observe and record child language - Online data repository: CHILDES Advantages of the naturalistic approach - Data comparatively easy to collect - Shows language as it is used in context Disadvantages - Rare structures may not be collected - How can we tell what a child s mental grammar will accept as grammatical? 19
6. Methods in acquisition research Experimental approach - Explicitly test children s ability to produce, comprehend, or imitate language Advantages of this approach - Can study comprehension - Can investigate specific linguistic structures Disadvantages - Can be difficult to design successful experiments for children - The relatively artificial context may affect aspects of children s language behavior 20
6. Methods in acquisition research Examples of experimental methods used in child language research BabyLab U Potsdam Acquisition Lab U Maryland Linguistics Penn Infant Language Center U Pennsylvania 21