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Language Sponges
About 3,000 new words per year, especially in the primary grades
As many as 8 new words per day
Learning words
12 ms first words
2 yrs 200 words
3 yrs 1,000 words
6 yrs 15,000 words
How do they do it (and what are they doing)?
Language Sponges Learning words
General patterns and observations Proposed Strategies
Fast mapping Whole object Mutual exclusivity
Learning Syntax Learning Morphology
Early word learning
Developed in systematic ways Not simply imitation, rather are creative Learned importance of consistency of names
First words (Around 10-15 months) 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 typically appear before verbs
Semantic Development
1-general names “dog”
2- specific names “mommy”
3-action words 4-modifiers
“red” 5-personal/social
“yes, no, please” 6-functional
“what”
Naming “Explosion”
Semantic Development Word Invention
to broom (to sweep) to fire (to burn) to scale (to weigh) a fix-man (a mechanic) a tooth-guy (a dentist) a locker (a lock) bum wiper (bathroom tissue) yester-minute (a minute ago)
Semantic Development
Extension Finding the appropriate limits of the meaning of
words Underextension
Applying a word too narrowly Overextension
Applying a word too broadly
Applying the words to referents
Semantic Development
Later words: 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)
Extensions of meaning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”
Extensions of meaning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”
Extensions of meaning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”2:0,10 “moo-ka” “hosh”
Extensions of meaning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”2:0,10 “moo-ka” “hosh”2:0,20
“biggie googie”
Extensions of meaning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”2:0,10 “moo-ka” “hosh”2:0,20
“biggie googie”
One-word-per-referent heuristic 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
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”2:0,10 “moo-ka” “hosh”2:0,20
“biggie googie”
Expansion and contraction can occur at the same time
Strategies for learning
1:9,111:10,18
“tee”
1:11,1
1:11,2“googie”
1:11,24
1:11,25 “tee/hosh”1:11,26 “hosh”1:11,27 “pushi”2:0,10 “moo-ka” “hosh”2:0,20
“biggie googie”
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
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
FrogFrog?
Green?Ugly?
Jumping?
Learning word meanings
Fast mapping Using the context to guess the meaning of a word
Learning words
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
Constraints on Word Learning
Perhaps children are biased to entertain certain hypotheses about word meanings over others
These first guesses save them from logical ambiguity Get them started out on the right track
Markman (1989)
Object-scope (whole object) constraint Taxonomic constraint Mutual exclusivity constraint
Object-scope (whole object) constraint Words refer to whole objects rather than to parts of
objects
Strategies for learning
Dog
‘Show me another lux’
‘Here is a lux’
Taxonomic constraint Words refer to categories of similar objects Taxonomies rather than thematically related obejcts
Strategies for learning
But in ‘no-word’ conditions, they would be shown the first picture
See this? Can you find another one?
Strategies for learning
4 and 5 year olds' choice of theme vs. category
-20
10
40
70
100
No word condition Novel word condition% Theme / Category
ThemeCategory
Strategies for learning
they choose the corkscrew because it is a less well known object for which they
don’t have a label yet.
‘Show me a dax’:
Mutual exclusivity constraint (Markam and Watchel 1988)
Each object has one label & different words refer to separate, non-overlapping categories of objects
An object can have only one label
Strategies for learning
Problem with constraints
Most of the constraints proposed apply only to object names.
What about verbs? (Nelson 1988) There have been cases where children have been
observed violating these constraints Using for example the word ‘car’ only to refer to ‘cars moving
on the street from a certain location’ (Bloom 1973) The mutual exclusivity constraint would prevent
children from learning subordinate and superordinate information (animal < dog < poodle)
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.
Language explosion continues
Proto-syntax (?) Holophrases
Single-word utterances used to express more than the meaning usually attributed to that single word by adults
Language explosion continues
“dog” might refer to the dog is drinking water
May reflect a developing sense of syntax, but not yet knowing how to use it
Controversial claim (e.g., see Bloom, 1973)
Syntax Basic child grammar (Slobin, 1985)
Similarities across all languages Mean length of utterance (MLU) in morphemes
Take 100 utterances and count the number of morphemes per utterance
Language explosion continues
Daddy coming. Hi, car. Daddy car comed. Two car outside. It getting dark. Allgone outside. Bye-bye outside.
# morphemes: 3, 2, 4, 3, 4, 2, 2‘-ing’ and ‘-ed’ separate morphemes‘allgone’ treated as a single word
MLU = morphemes/utterances = 20/7 = 2.86
Syntax Roger Brown proposed 5 stages
Stage 1: Telegraphic speech (MLU ~ 1.75; around 24 months) One and two word utterances Debate: learning semantic relations or syntactic (position rules)
Language explosion continues
Children in telegraphic speech stage are said to leave out the ‘little words’ and inflections:
e.g. Mummy shoe NOT Mummy’s shoe Two cat NOT two cats
More than two words Stages 2 through 5
Stage 2 (MLU ~2.25) begin to modulate meaning using word order (syntax)
Later stages reflect generally more complex use of syntax (e.g., questions, negatives)
Language explosion continues
Syntax Roger Brown proposed 5 stages
Innateness account Pinker (1984, 1989)
Semantic bootstrapping
How do kids learn the syntax?
Child has innate knowledge of
syntactic categories and linking rules
Child learns the meanings of
some content wordsChild constructs some semantic representations
of simple sentences Child makes guesses
about syntactic structure based on surface form and semantic meaning
“It is in the stimulus” accounts Children do not need innate knowledge to learn grammar
Speech to children is not impoverished (Snow, 1977) Children learn grammar by mapping semantic roles (agent, action,
patient) onto grammatical categories (subject, verb, object) (e.g. Bates, 1979)
How do kids learn the syntax?