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  1. Today Nonlearnable production grammars: ranking reversals and reinterpretation of contrast Fijian Malayalee English Korean liquids

  2. First--review

  3. Our job in processing speech… Turn sound waves (vibration of air molecules) into meaning. To do this, we need to interpret the acoustic cues in the sound waves in order to translate sound waves into phonological representations.

  4. From sound to meaning Acoustic Form (perception) Phonological Representation (production) Phonetic Representation

  5. Questions When a speaker mispronounces a foreign word, is the mispronunciation due to misproduction? misperception?

  6. Japanese example English Japanese [beɪsbɔl] [be:suboru]

  7. First Possibility: Accurate Perception, Inaccurate Production • Japanese listener hears [beɪsbɔl]. • /beɪsbɔl/ is input to Japanese production grammar, which disallows certain segments and consonant codas. • Production grammar transforms /beɪsbɔl/ to [be:suboro].

  8. Second Possibility: Inaccurate Perception, Accurate Production • Japanese listener hears [be:suboru]. • /be:suboru/ is input to Japanese production grammar, and is a legal Japanese structure. • Output of production grammar is [be:suboru].

  9. Evidence for Misperception of /r-l/ Miyagawa et al. (1975) (and others): English listeners perceived /r-l/ continuum categorically; Japanese listeners did not have clear category boundaries for /r/ vs. /l/.

  10. Effect of Native Language In English, the [r] –[l] contrast is significant: ‘rip’ vs. ‘lip’ In Japanese, this contrast is not significant: Japanese employs a single liquid pronounced more like [r] in certain contexts, more like [l] in other contexts.

  11. Misperception even with good production Sheldon & Strange (1982): Japanese students of English who produced an English-like /r/-/l/ contrast still performed poorly on discrimination (even of their own [ra], [la] tokens).

  12. Evidence for misperception of consonant sequences as CVC Dupoux et al. (1999): Japanese listeners did not reliably distinguish forms like [ebzo] – [ebuzo] (they heard ‘illusory vowels’). French listeners DID distinguish [ebzo]-[ebuzo].

  13. Effect of Native Language In French (and English), the contrast between VCCV and VCVCV is significant: ‘NAFTA’ vs. ‘taffeta’ In Japanese, no such contrast exists because obstruents ([f], [b], [z], etc.) are not possible in syllable coda.

  14. Persistent misperception Takagi & Mann (1995): adult Japanese speakers who had lived in the US and been using English daily for more than 12 years still performed below English speakers on perception tests.

  15. Our basic question Do foreign language modification patterns come from misperception or misproduction? And how can you tell (short of doing perception experiments for each case)?

  16. Criterion: Learnability • OT provides a model of acquisition. • This model allows us to determine whether a particular grammar is learnable from a set of input data.

  17. Acquisition of a production grammar THE LEARNER’S TASK: To discover constraint rankings.

  18. DEFAULT RANKING M >> F e.g., NoComplexOnset >> Max (don’t delete) Predicts underlying /sno/ mapped to [so].

  19. Constraint reranking: error-driven If the learner hears a marked structure (e.g. [sno]), (s)he will rerank the constraints. Max >> NoComplexOnset

  20. Learning Fx >> Fy In order to learn relative ranking of faithfulness constraints, learner must have evidence of unfaithful mappings.

  21. F >> F • If /sno/ > [so], then deletion is the preferred repair. Dep (don’t insert) >> Max (don’t delete) • If /sno/ > [sono], then insertion is the preferred repair. Max (don’t delete) >> Dep (don’t insert)

  22. Is a grammar learnable? Rankings must be either universal default (M>>F) or learnable from the data

  23. Case Study 1: Fijian stop adaptation (Kenstowicz 2003) Fijian: ‘balloon’ [balun] > [mbaluni] (*[paluni])

  24. Fijian NL (native language) grammar • M >> F constraint banning fully oral stop [b] outranks faithfulness What choices do Fijians have as substitutes for [b]?

  25. Fijian Native Language Phonemes Voiceless unaspirated /p/ Voiced prenasalized /mb/

  26. Why do Fijians choose /b/ > [mb], not [p]? Modification grammar: Ident[voice] >> Ident[nasal] (maintaining voice specification is more important than maintaining nasal specification)

  27. Where does this ranking come from? • Ident[voice] >> Ident[nasal] • From English? • From Fijian? • From universal grammar?

  28. PROBLEM! Universal default (Steriade 2001): Ident[nasal] >> Ident[voice] Fijian adapters Ident[voice] >> Ident[nasal]

  29. Alternative analysis: misperception • Kenstowicz 2003: Word-initial Fijian stops are often only slightly prenasalized (or not at all prenasalized). • NL perception grammar interprets word-initial voiced stop as prenasalized. (Voicing is a cue for prenasalization).

  30. Fijian stop adaptation as NL transfer • Fijian NL perception grammar interprets the English /p-b/ contrast in terms of Fijian /p-mb/ contrast.

  31. Case Study 2: Malayalee English

  32. Malayalee English (Mohanan & Mohanan 2003) English intervocalic voiceless stops Rippo:RT ‘report’ bekkar ‘baker’ pæ:kket ‘packet’

  33. Malayalam NL grammar Markedness constraint: *V[-voice]V: no voiceless stops in intervocalic position (also active in Korean) M >> F

  34. Malayalee English grammar Ident(voice) >> Ident(length) Maintaining voicing specification is more important than maintaining length specification

  35. PROBLEM! Malayalam ranking: *VkV>>Ident(length) >> Ident(voice) /VkV/ > [VgV] Malayalee English Ranking: *VkV>> Ident(voice) >>Ident(length) /VkV/ > [VkkV]

  36. Learnability problem • Evidence for reranking of length faithfulness and voicing faithfulness • No evidence from Malayalam • No evidence from English

  37. BUT-- The adaptation pattern is explainable as transfer of Malayalam perception grammar.

  38. Malayalee English, continued English intervocalic voiced stops bæ:bu:n ‘baboon’ iRigeet ‘irrigate’ figaR ‘figure’

  39. Alternative analysis: misperception Malayalam speakers interpreted English contrast in terms of Malayalam contrast English Malayalam voice contrast length contrast VkV /VkkV/ > [VkkV] VgV /VkV/ > [VgV]

  40. Malayalam cues for singleton-geminate contrast (Local & Simpson (1999) 1. Voicing: singletons are voiced intervocalically. 2. Vowel duration: vowels longer before singletons than before geminates mean V duration: 76.5 msec before singleton 58.8 msec before geminates

  41. English cues for voicing contrast 1. Voicing 2. Vowel duration: vowel is longer before voiced consonant.

  42. Cue Confusion • English: shorter vowel > voiceless consonant. lack of voicing > voiceless consonant. • Malayalam: shorter vowel > geminate consonant. lack of voicing > geminate consonant.

  43. Note: English voice contrast is not maintained in all contexts ‘possible’ > [pɔ:sibL] ‘impossible’ > [imbɔ:sibL] Malayalee English ranking: *NC[-voice] >> Ident(voice)Foreign>> *V[-voice]V How could this be learned?

  44. Interim summary • Fijian and Malayalee English adaptation patterns required specific production grammar rankings. • These rankings were not learnable from the data of either the native or the foreign language.

  45. In Fijian, the adaptation rankings contradicted putative universal rankings (so they cannot be default). • In Malayalee English, the adaptation rankings contradicted the NL rankings.

  46. In both languages, the adaptation pattern could be better understood as interpretation of the foreign language acoustic cues in terms of a native language contrast.

  47. If misproduction does stem from misperception… At what level of processing does misperception occur?

  48. Sources of Misperception Do listeners • accurately perceive the acoustic differences, but miscategorize them? OR • fail to perceive acoustic differences that are relevant for native language contrasts?

  49. Native Language Neural Commitment Hypothesis (Kuhl 2004) Early exposure to a language produces a “neural commitment” to the acoustic cues that are important for that language. This neural commitment leads to efficient processing of NL contrasts (but not of FL contrasts).

  50. But what if you start early? Pallier et al. (1997) tested ability of fluent Spanish-Catalan bilinguals to discriminate [e] and [ɛ], which contrast in Catalan but not in Spanish.