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PSY 369: Psycholinguistics
Language Acquisition:
Learning words, syntax, and more
Learning word meanings Learning words (a brief review)
One word stage Idiomorphs Over and under extension of meaning Generally:
one word per referent If it doesn’t work, pick a new word
How do the kids match the words to the referents?
Indeterminacy: Frog
FrogFrog?
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
FrogFrog?
Green?Ugly?
Jumping?
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
‘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 Remember: word order is important! 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
Language explosion continues
0
1
2
3
4
5
6
0 10 20 30 40 50 60
age (months)
MLU
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) Similar meaning to words used in 1 word stage:
Negation, nonexistence, call attention Soon branches out to other meanings (Brown, 1973)
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?
Morphology Typically things inflections and prepositions start around
MLU of 2.5 (usually in 2 yr olds) Wug experiment (Berko-Gleason, 1958)
Language explosion continues
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
Here is a wug.
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.QuickTime™ and a
TIFF (LZW) decompressorare needed to see this picture.
Now there are two of them.
There are two _______.
Morphology Lists of forms Rules Overregularization
Language explosion continues