1. PSY 369: Psycholinguistics
Language Acquisition:
Learning words

2. 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

3. 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

4. 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 words
Volume and pitch of voice not yet well-controlled

5. 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 words
About 90% of what child says should be intelligible
Verbs begin to predominate

6. 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)

7. 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

8. 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

9. 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

10. Early speech production
First words
Around 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

11. Early speech production
First words
Around 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

12. 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

13. 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)

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

15. 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.

16. 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

17. 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

18. 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

19. Extensions of meaning
“tee”

20. Extensions of meaning
“tee”
1:9,11

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

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

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

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

25. 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

26. 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”

27. 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”

28. 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”

29. 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”

30. 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

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

32. 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

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

34. Indeterminacy: Frog
Frog
Frog?
Green?
Ugly?
Jumping?

35. 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?

36. 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

37. 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

38. 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.