PSY 369: Psycholinguistics Language Acquisition: Learning words

Typical language development 12 Months Uses one or more words with meaning (this may be a fragment of a word) Understands simple instructions, especially if vocal or physical cues are given Practices inflection Is aware of the social value of speech

Typical language development 18 Months Has vocabulary of approximately 5-20 words Vocabulary made up chiefly of nouns Some echolalia (repeating a word or phrase over and over) Is able to follow simple commands

Typical language development 24 Months Can name a number of objects common to his surroundings Is able to use at least two prepositions Combines words into a short sentence Vocabulary of approximately 150-300 words Volume and pitch of voice not yet well-controlled

Typical language development 36 Months Use pronouns I, you, me correctly Is using some plurals and past tenses Knows at least three prepositions Handles three word sentences easily Has in the neighborhood of 900-1000 words About 90% of what child says should be intelligible Verbs begin to predominate

Language Sponges Lots of individual differences But there is also a consistent pattern On average, American children say their first word at around 13 months, experience a vocabulary spurt at around 19 months, and begin to produce simple sentences at around 24 months. However, the bars around the means show that there is great variability in when different children achieve each of these milestones. (Adapted from Bloom, 1998)

Language Sponges Learning words 12 ms first words 2 yrs 200 words About 3,000 new words per year, especially in the primary grades As many as 8 new words per day Production typically lags behind comprehension

Vocabulary growth Methods used to study this Observational data (60s to present) Diary studies Parents record their kids language development Taped language samples (Roger Brown) Small numbers of children (Eve, Adam, Sarah) Went to home every month made tape recordings Extensive study needed Hard to kids to “say all the words you know” or “say a question” Early phonological production isn’t like adult production, often need to take great care deciding what the child meant Large database CHILDES Many kids, many languages, including children with language difficulties CHILDES - the child language data exchange system

Early speech production Of course he said “arf.” What else did you expect his first word to be? CHILDES - the child language data exchange system

Early speech production First words Around 10-15 months (lots of individual differences) Emergence of systematic, repeated productions of phonologically consistent forms Idiomorphs - personalized words Developed in systematic ways Sometimes simplifications of adult speech Or relate to sounds of the objects Demonstrate Creative, not simply imitation Learned importance of consistency of names CHILDES - the child language data exchange system

Early speech production First words Around 10-15 months (lots of individual differences) Emergence of systematic, repeated productions of phonologically consistent forms Idiomorphs - personalized words Typically context bound (relevant to the immediate environment) Important people Objects that move Objects that can be acted upon Familiar actions Nouns before verbs CHILDES - the child language data exchange system Charlie’s words

Semantic Development 1-general names 2- specific names 3-action words dog 2- specific names mommy 3-action words 4-modifiers red 5-personal/social yes, no, please 6-functional what

Later words Then: Children come to use words in more adult-like ways Words start to be used in wider range of contexts Children use wider range of word types: referential words (ball, doggie, chair) proper names (Mummy, Spot) actions (open, wash, tickle) properties, states, qualities (more, gone, up, on, dirty) social-pragmatic words (no, please) few ‘frozen’ phrases (all gone, what’s that)

Early speech production Transition to speech No. … my fis. No. My fis! This is your fis? Yes, my fis. Your fis? Oh, your fish.

Early speech production Transition to speech This is your fis? No, … my fis. Can’t hear the difference? Rejects adult saying fis Can’t produce the correct sounds? Sometimes, but evidence suggests not always the case More general process of simplification “frees up” resources for concentrating on other aspects of language learning Your fis. No, my fis. Oh, your fish. Yes, my fis.

Early speech production Transition to speech Early words Common Phonological processes Reduction Delete sounds from words Coalescence Combine different syllables into one syllable Assimilation Change one sound into a similar sound within the word Reduplication One syllable from a multi-syllabic word is repeated

Learning word meanings Learning words Fast mapping Using the context to guess the meaning of a word Please give me the chromium tray. Not the blue one, the chromium one. All got the olive tray Several weeks later still had some of the meaning

Learning word meanings Learning words Extension Finding the appropriate limits of the meaning of words Underextension applying a word too narrowly Overextension applying a word too broadly

Extensions of meaning “tee”

Extensions of meaning “tee” 1:9,11

Extensions of meaning “tee” 1:9,11 1:10,18

Extensions of meaning “tee” 1:9,11 1:10,18 1:11,1 “googie”

Extensions of meaning “tee” 1:9,11 1:10,18 1:11,1 “googie” 1:11,2

Extensions of meaning “tee” “googie” 1:9,11 1:10,18 1:11,1 1:11,2 1:11,24

Extensions of meaning “tee” “googie” “tee/hosh” 1:9,11 1:10,18 1:11,1 1:11,2 1:11,24 “tee/hosh” 1:11,25

Extensions of meaning “tee” “googie” “tee/hosh” “hosh” 1:9,11 1:10,18 1:11,1 “googie” 1:11,2 1:11,24 “tee/hosh” 1:11,25 1:11,26 “hosh”

Extensions of meaning “tee” “googie” “tee/hosh” “hosh” “pushi” 1:9,11 1:10,18 1:11,1 “googie” 1:11,2 1:11,24 “tee/hosh” 1:11,25 1:11,26 “hosh” 1:11,27 “pushi”

Extensions of meaning “tee” “googie” “tee/hosh” “hosh” “pushi” 1:9,11 1:10,18 1:11,1 “googie” 1:11,2 1:11,24 “tee/hosh” 1:11,25 1:11,26 “hosh” 1:11,27 “pushi” 2:0,10 “moo-ka” “hosh”

Extensions of meaning “tee” “googie” “tee/hosh” “hosh” “pushi” 1:9,11 1:10,18 1:11,1 “googie” 1:11,2 1:11,24 “tee/hosh” 1:11,25 1:11,26 “hosh” 1:11,27 “pushi” 2:0,10 “moo-ka” “hosh” 2:0,20 “biggie googie”

Strategies for learning Things to notice One-word-per-referent If a new word comes in for a referent that is already named, replace it Exception to that was “horse,” but it only lasted a day here

Strategies for learning Things to notice Over and under Extension can occur at the same time

Strategies for learning Things to notice Child tries different things, if a word doesn’t work then try something else e.g., hosh didn’t for for the large dog, switched to biggie doggie

Learning word meanings Learning words Learning the meanings of words Quine’s problem Whole object Mutual exclusivity

Indeterminacy: Frog Frog Frog? Green? Ugly? Jumping?

Quine’s gavagai problem The problem of reference: a word may refer to a number of referents (real world objects) a single object or event has many objects, parts and features that can be referred to Frog Frog? Green? Ugly? Jumping?

Constraints on Word Learning Markman (1989) Perhaps children are biased to entertain certain hypotheses about word meanings over others These first guesses save them from logical ambiguity, and keep them logical confusion, and get them started out on the right track

Strategies for learning Object-scope (whole object) constraint words refer to whole objects rather than to parts of objects Taxonomic constraint words refer to categories of similar objects Mutual exclusivity constraint each object has one label & different words refer to separate, non-overlapping categories of objects

Language explosion continues The language explosion is not just the result of simple semantic development; the child is not just adding more words to his/her vocabulary. Child is mastering basic syntactic and morphological rules.