Ling 240: Language and Mind

1. Ling 240: Language and Mind Acquisition of Phonology

2. English [p] [b] [ph]

3. Hindi [p] [b] [ph]

4. English Japanese [l] [l] [r] [r]

5. Voice onset time VOT = the time between the release of a stop and the voicing of a following vowel

6. Voice Onset Time (VOT) 60 msec

7. Discrimination D 0ms 20ms D D 20ms 40ms T T 40ms 60ms T

8. Categorization of speech sounds • We group sounds into categories, despite physical variability • Some physical differences are mentally represented as “not different”; others as “different” • Is categorical perception innate? • How are mental categories acquired?

9. High Amplitude Sucking Procedure • Initially sucking rate increases (novelty) • Then decreases • Decline in response =habituation LSCP Infant Lab

10. High Amplitude Sucking Procedure When sucking rate declines to a set point(habituation criterion), auditory stimulus is changed LSCP Infant Lab

11. High Amplitude Sucking Procedure • If sucking rate increases, • then we know the infant has detected the change • The renewed response =dishabituation LSCP Infant Lab

12. Newborns are universal listeners • Infants perceive speech categorically • Newborns are sensitive to almost every phonological distinction yet tested

13. Newborns are universal listeners • In contrast, adults have difficulty discriminating speech sounds that are not contrastive in their native language

14. Hindi contrasts • [dããt] tooth • [DããT] scold, be angry with • [taal] ‘musical note’ • [Taal] ‘to ignore’

15. Newborns are universal listeners • English infants can distinguish Hindi /d/ and /D/ • Japanese infants can distinguish between /l/ and /r/

16. Studies by Werker et al Infants are universal listeners but adults can’t discriminate non-native phonemic contrasts Then there must be a decline across age Questions: what is the role of experience? when exactly does this decline happen? is this decline a critical period effect?

17. Testing Across the Lifespan • young infants • older infants • children and adults Habituation (High Amplitude Sucking) Conditioned Head Turn Paradigm Just ask them: “Same or different?”

18. Visual Reinforcer (VR) Toy that lights up and moves at the experimenter’s command Controls for sound stimuli and the VR

19. Conditioned Head Turn • Child hears Stimulus 1 (/ba/) repeatedly • Then Stimulus 2 is presented (/da/) • If child detects difference, he should turn to look at the visual reinforcer when the stimulus changes • If child does not detect it, he shouldn’t turn

20. Conditioned Head Turn Paradigm Kuhl Lab, U Washington, 1992

21. Werker 1995 Subjects:Hindi adults English Adults English 6-8 month-olds Testing /ba/ vs. /da/ /Ta/ vs. /ta/ /tha/ vs. /dha/

22. Werker 1995 /ba/ vs. /da/ Hindi and English /Ta/ vs. /ta/ Only Hindi /tha/ vs. /dha/ Only Hindi

23. Results Werker, 1995

24. Questions When does decline in performance take place? What exactly is responsible for the decline? Does Critical Period play a role?

25. General Methodology question We observe that infants behave one way and adults behave another way. Goal: We want to know what changes at what point in time. What are some ways of obtaining this data?

26. Werker & Tees 1984 • Test infants of different ages (Cross-sectional) • Test the same group of infants at different points in time (Longitudinal) • 6-8 months • 8-10 months • 10-12 month

27. Werker & Tees 1984: Nthlakampx Native American language spoken by about 200 speakers (in 1984) in British Columbia—also known as Thompson or Salish Nthlakampx glottalized velar vs glottalized uvular ejectives [‘ki] vs [‘qi] Velar ‘k.. Uvular ‘q…

28. Results Werker & Tees, 1984

29. Werker studies: Conclusion Ability to perceive non-native contrasts declines in 1st year Werker and Tees 1984

30. What is responsible for the change? How do babies become adults?

31. First proposal: Maintenance/Loss Hypothesis role of experience is to maintain perceptual sensitivities lack of exposure leads to loss of perceptual ability

32. Maintenance/Loss Model Ability Experience No experience 1 year Time

33. Problems for the Maintenance/Loss Hypothesis Prediction? Decline in sensitivity following lack of exposure should be permanent and absolute

34. Problems for the Maintenance/Loss Hypothesis Predictions are not borne out: (1) Adults CAN perceive non-native contrasts in (perceived) non-speech tasks Zulu clicks The link to listen to Zulu clicks http://www.youtube.com/watch?v=gytCi5a7AJg sounds in isolation (not syllables)

35. Problems for the Maintenance/Loss Hypothesis Predictions are not borne out: (2) Children older than 12 months can move to a new country and acquire native phonology

36. Alternative Hypothesis: Functional Reorganization no absolute hardware changes in auditory system development of a linguistic system that imports a subset of the contrasts from the auditory system

37. Conclusions So, what changes during the first year? Answer: the baby starts to acquire a linguistic system As babies acquire a linguistic system (words) in their first year, they “learn” which distinctions need to be represented in that system