1. Phonetic Detail in Developing Lexicon Daniel Swingley 2010/11/051Presented by T.Y. Chen in 599

2. The issue Do infants/children store every piece of phonetic details of words in the lexicon in the very beginning stage of phonological acquisition? 2010/11/05Presented by T.Y. Chen in 5992

3. Continuous debates 6-8 mo Infants are broadly sensitive to different sound categories, and are gradually declined to perceive only their native categories. Perceptual Assimilation Model (Best 1994) Native Language Magnet (Kuhl 1995) 2010/11/05Presented by T.Y. Chen in 5993

4. Continuous debates However… The stimuli used in the experiments do not match the natural variability of speech. Translating an acoustic sequence into segments does not entail retaining (all of) them. 2010/11/05Presented by T.Y. Chen in 5994

5. Continuous debates Jusczyk & Aslin (1995): 7.5 mo infants can encode initial segment (e.g. /k/ in cup vs. /t/ in tup) by listening just a few tokens. Halle & de Boysson-Bardies (1996): 11 mo French infants have the preference of ponjour and vonjour after listening to bonjour. (A global representation of [+labial]) 2010/11/05Presented by T.Y. Chen in 5995

6. Continuous debates Naming task fails for some chirldren ranged from 10 to 28 mo (e.g. Matthews 1997). Dehabituation task fails for 14 mo children (Stager & Werker 1997). Walley (1993) assumes that children with small vocabularies might represent cat as [+abrupt onset], or cap as [+labial]. 2010/11/05Presented by T.Y. Chen in 5996

7. Continuous debates Theoretical phonologists suggest the infants’ lexical representation is more or less identical to the adult form. Lexicon Optimization in Optimality Theory assumes all of the adult forms are stored into lexicon faithfully. 2010/11/05Presented by T.Y. Chen in 5997

8. Author’s view The results in the previous studies are not entirely reliable… Metalinguistic responses are required; it is just difficult to get any overt response… Production tasks are not ideal to test children’s receptive forms in the lexicon… 2010/11/05Presented by T.Y. Chen in 5998

9. Experiment Design Visual fixation: no overt response is needed. If children can discriminate phonetic details, the visual fixation on the target picture will be different. Participants: Dutch learning children ranged from 18;07 (months;days) to 20;17. 2010/11/05Presented by T.Y. Chen in 5999

10. Hypothesis I At first, children have only global representations of words (e.g. [+labial] for bonjour), unless they also learn some minimal-pair words (e.g. vonjour) that help them to distinguish one sound from the other. 2010/11/05Presented by T.Y. Chen in 59910

11. Experiment I Stimuli: CP - bal ‘ball’, beer ‘bear’ MP – onset substitution of /g/ and /d/ (Only dal ‘valley’ is a real word in Dutch) If the children only have global representations of the two words, they should not be able to distinguish, for example, beer from geer or deer. 2010/11/05Presented by T.Y. Chen in 59911

12. Experiment I Task: Pictures of ball and bear are presented respectively; children look at the pictures and listen to the stimuli of Waas is de [target] (Where is the [target]). 2010/11/05Presented by T.Y. Chen in 59912

13. Experiment I Result: 2010/11/05Presented by T.Y. Chen in 59913

14. Experiment I Results: Children fixate the targets longer in the CP condition (p=.03). Children do not need to know any minimal- pair word to distinguish sounds; the phonetic details of a word are stored in the lexicon, which can be used for the sound discrimination. 2010/11/05Presented by T.Y. Chen in 59914

15. Hypothesis II Children might learn a minimal-pair word due to misparsing of word boundaries. For example, peer can be learned from a longer word #___+peer# as a possible minimal-pair word of beer. 2010/11/05Presented by T.Y. Chen in 59915

16. Experiment II Stimuli: CP – baby ‘baby’, beker ‘cup’ MP – Word-medial substitution with /d/ and /g/ (e.g. bady or bagy). 2010/11/05Presented by T.Y. Chen in 59916

17. Experiment II 2 minimal-pair words for beker are zeker and beter. Yet there is no possible minimal-pair word for baby, even with misparsing: e.g. No instance of ba#gy or #___+bagy# 2010/11/05Presented by T.Y. Chen in 59917

18. Experiment II Word-medial substitution rules out the possibility that children discriminate sounds solely by the very first part of a word. For example, children might know the target is baby instead of car by just hearing ba… 2010/11/05Presented by T.Y. Chen in 59918

19. Experiment II Result: 2010/11/05Presented by T.Y. Chen in 59919

20. Experiment II Results: The children again fixate longer on the target picture in the CP condition! (p=.03) No correlation with the children’s receptive and productive vocabularies reported by their parents (r=.06, r=.07). 2010/11/05Presented by T.Y. Chen in 59920

21. Author’s Conclusions Children store every phonetic detail in the lexicon; acquiring minimal-pairs is not a prerequisite for them to distinguish sounds. Why do some children fail to demonstrate the sound discrimination? They do encode the details, but they may forget which form corresponds to which word. 2010/11/05Presented by T.Y. Chen in 59921

22. Follow-up Question I Is it enough to make the conclusion by testing just one single segment in each experiment? If children retains phonetic details completely, shouldn’t we test the discrimination of every segment in the stimuli? 2010/11/05Presented by T.Y. Chen in 59922

23. Follow-up Question II Does the phonotactic distribution help the children to identify the sound contrasts? For example, in English, none of baby, pig, beckon, happy, brush, and pickles can form minimal- pairs, but they show a /b/-/p/-/k/ onset contrast. 2010/11/05Presented by T.Y. Chen in 59923

24. Follow-up Question III Is it possible that these children ‘watch’ too many English TV shows and learn/hear some minimal-pair words from them?? 2010/11/05Presented by T.Y. Chen in 59924