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

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

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Today

Nonlearnable production grammars: ranking reversals and reinterpretation of contrast

FijianMalayalee EnglishKorean liquids

First--review

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.

From sound to meaning

Acoustic Form

(perception)

Phonological Representation

(production)

Phonetic Representation

Questions

When a speaker mispronounces a foreign word, is the mispronunciation due to

misproduction?

misperception?

Japanese example

English Japanese

[beɪsbɔl] [be:suboru]

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].

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].

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/.

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.

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).

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].

Effect of Native Language

In French (and English), the contrast betweenVCCV 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.

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.

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)?

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.

Acquisition of a production grammar

THE LEARNER’S TASK:

To discover constraint rankings.

DEFAULT RANKING

M >> F

e.g., NoComplexOnset >> Max (don’t delete)

Predicts underlying /sno/ mapped to [so].

Constraint reranking: error-driven

If the learner hears a marked structure (e.g. [sno]), (s)he will rerank the constraints.

Max >> NoComplexOnset

Learning Fx >> Fy

In order to learn relative ranking of faithfulness constraints, learner must have evidence of unfaithful mappings.

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)

Is a grammar learnable?

Rankings must be either

universal default (M>>F)

or

learnable from the data

Case Study 1: Fijian stop adaptation (Kenstowicz 2003)

Fijian:

‘balloon’ [balun] > [mbaluni] (*[paluni])

Fijian NL (native language) grammar

M >> F

constraint banning fully oral stop [b] outranks faithfulness

What choices do Fijians have as substitutes for [b]?

Fijian Native Language Phonemes

Voiceless unaspirated /p/

Voiced prenasalized /mb/

Why do Fijians choose /b/ > [mb], not [p]?

Modification grammar:

Ident[voice] >> Ident[nasal]

(maintaining voice specification is more important than maintaining nasal specification)

Where does this ranking come from?

Ident[voice] >> Ident[nasal]

From English? From Fijian? From universal grammar?

PROBLEM!

Universal default (Steriade 2001):

Ident[nasal] >> Ident[voice]

Fijian adapters

Ident[voice] >> Ident[nasal]

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).

Fijian stop adaptation as NL transfer

Fijian NL perception grammar interprets the English /p-b/ contrast in terms of Fijian /p-mb/ contrast.

Case Study 2: Malayalee English

Malayalee English (Mohanan & Mohanan 2003)

English intervocalic voiceless stops

Rippo:RT ‘report’

bekkar ‘baker’

pæ:kket ‘packet’

Malayalam NL grammar

Markedness constraint: *V[-voice]V:

no voiceless stops in intervocalic position (also active in Korean)

M >> F

Malayalee English grammar

Ident(voice) >> Ident(length)

Maintaining voicing specification is more important than maintaining length specification

PROBLEM!

Malayalam ranking:

*VkV>>Ident(length) >> Ident(voice)

/VkV/ > [VgV]

Malayalee English Ranking:

*VkV>> Ident(voice) >>Ident(length)

/VkV/ > [VkkV]

Learnability problem

Evidence for reranking of length faithfulness and voicing faithfulness

No evidence from Malayalam No evidence from English

BUT--

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

Malayalee English, continued

English intervocalic voiced stops

bæ:bu:n ‘baboon’

iRigeet ‘irrigate’

figaR ‘figure’

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]

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

English cues for voicing contrast

1. Voicing

2. Vowel duration: vowel is longer before voiced consonant.

Cue Confusion

English:

shorter vowel > voiceless consonant.

lack of voicing > voiceless consonant.

Malayalam:

shorter vowel > geminate consonant.

lack of voicing > geminate consonant.

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]VHow could this be learned?

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.

In Fijian, the adaptation rankings contradicted putative universal rankings (so they cannot be default).

In Malayalee English, the adaptation rankings contradicted the NL rankings.

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.

If misproduction does stem from misperception…

At what level of processing does misperception occur?

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?

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).

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.

Subjects included 2 groups

• bilinguals with Spanish as first language• bilinguals with Catalan as first language

Both groups • used both languages daily• were highly proficient in both languages• had been exposed to the second language

by age 6

Even for fluent bilinguals, mother tongue shaped perception

Subjects whose first language exposure was to Spanish were unable to reliably perceive the e/ɛ distinction.

In contrast, subjects whose first exposure was to Catalan DID perceive this contrast.

Hypothesis

Early exposure to a language makes the speech processing system sensitive (only?) to those acoustic cues that distinguish linguistically significant contrasts in the native language.

Case Study 3: Korean Pronunciation of English [r], [l]

[r] – [l] alternations in Korean

tal ‘moon’

tar-i ‘moon (nominative)’

/l/ and /r/ do not contrast in Korean

/l/ occurs in syllable coda

(word-finally and before a consonant)

/r/ occurs in syllable onset

(word-initially and between vowels)

Korean Liquid Alternation (Lee 2001)

a. /l/tal ‘moon’mal ‘horse’sal.ku ‘apricot’

b. /r/ta.r-i ‘moon (nom.)’

ma.r-i ‘horse (nom.)’ sa.ram ‘person’

How do Korean speakers interpret the English /l/ - /r/ contrast?

Possibility One: Accurate Perception, Inaccurate Production

According to Korean grammar:

Both /l/ and /r/ should be pronounced

as /l/ in syllable coda,

as /r/ in syllable onset.

Possibility One: Accurate Perception, Inaccurate Production

Korean production grammar forces intervocalic [l] and [r] to be pronounced as [r] in syllable onset:

‘cherry’ heard as /ceri/ pronounced as [ce.ri]?

‘cello’ heard as /celo/ pronounced as [ce.ro]?

Possibility Two: Inaccurate Perception, Accurate Production

Koreans do not perceive [r] – [l] contrast:

‘cherry’ heard as /ceri/ pronounced as [ce.ri]?

‘cello’ heard as /cero/ pronounced as [ce.ro]?

If Korean speakers simply map English phonemes to Korean phonemes…

The [r] – [l] contrast should not be maintained by Korean speakers—it should be lost either in perception or in production.

But what actually happens?

Korean Adaptation of English liquids (Kenstowicz 2005, Oh 2005)

intervocalic /r/ > [r]

kʰo:rasɨ ‘chorus’

orenʒi ‘orange’

misɨtʰeri ‘mystery’

BUT

intervocalic /l/ > [ll]

cʰello ‘cello’

sillikʰon ‘silicon’

kʰolla ‘cola’

Though there is some variation

[kilo, killo] ‘kilo’

Oh (2005): influence of spelling

orthographic ‘ll’ > [ll] 99.9%

orthographic ‘l’ > [ll] 84%

So strong trend toward [ll], regardless of spelling.

Puzzle

/r/ - /l/ contrast is not significant in Korean, but Koreans maintain it in English words.

English [r] > Korean [r] (kʰo:rasɨ ‘chorus’)

English [l] > Korean [ll] (kʰolla ‘cola’)

But Korean has [r] – [ll] contrast

Oh (2005)

mu.ri ‘group’ mul.li ‘physics’

mə.ri ‘head’ məl.li ‘far’

English Contrast Korean Contrast

/r/ > /r ~ l/

/l/ > /ll/

although English (initial) [r] has longer F1 transition than [l] (O’Connor et al. 1957)

Does the change from /l/ to /ll/ take place in production?

Optimality Theory says it can’t.

Korean Native Language Grammar

Lee (2001)

[l] only if moraic (attached to coda) >>DepMora (don’t change duration) >>

Ident[lateral] (don’t change laterality)

(=>To repair illegal structure V[l]V, change it to V[r]V)

To get pattern in which V[l]V is repaired by changing it to V[ll]V, we would need to rerank the constraints.

Reranking to describe /l/ > [ll]

Native Language ranking:

[l]=moraic >> Ident(length) >> Ident(lat)

Interlanguage Ranking:

[l] =moraic >> Ident(lat) >> Ident(length)

Problem

There is no data that would cause the learner to rerank these constraints in this way—nothing about English provides evidence that changing duration is a better way to repair an illegal structure than changing laterality.

So..

Analysis assuming accurate perception, inaccurate production is ruled out.

The theory of grammar learning provides no way for learners to come up with a grammar that would transform V[l]V to V[ll]V.

Inaccurate perception?

Do Korean listeners actually hear English [VlV] as [VllV]?

The relevant cues for Korean listeners:

1. presence/absence of laterality (mainly F3)

2. consonant duration

muri = [-lateral, short] ‘group’

mulli = [+lateral, long] ‘physics’

Questions

How important is duration in signalling the VrV – VllV contrast for Korean listeners?

Would a difference in laterality alone be enough to signal this contrast?

Kim (2007): [lateral] alone is enough

Subjects: monolingual speakers of Korean

Kim (2007) Stimuli

1. Real words containing VllV, e.g. [mulli]

(legal in Korean).

2. Real words containing VrV, e.g. [muri] (legal in Korean).

3. ‘Words’ containing VlV, e.g. [muli] (illegal in Korean), made by shortening the [l] in V[ll]V words.

Kim (2007) Task

Listeners heard (edited) words like [muli].

Forced choice: Did you hear

[muri] (‘group’) or [mulli] (‘physics’)?

Results

[VlV] heard as

[VllV] 324 90%

[VrV] 36 10%

Kim (2007) results suggest that

Korean listeners pay at least as much attention to the laterality as to consonant duration.

Laterality alone is enough to cause Korean listeners to classify even a short [l] as [ll].

BUT

Does this mean that Korean listeners actually do not hear the differences between English [l] and Korean [ll]?

ERP

Event-Related Potentials: A non-invasive method of measuring electrical activity in the brain during low level processing (Luck 2005).

Electrode Cap

Mismatch Negativity

The Mismatch Negativity (MMN) indicates brain response to change in an auditory stimulus.

MMN is elicited even in the absence of attention to stimulus (e.g., while watching a silent movie).

Oddball Paradigm

ba - ba - ba - ba - pa

standard deviant

MMN is typically elicited 150-250 msec after onset of deviance.

Discrimination tasks tap into conscious categorization.

ERP taps into involuntary, pre-attentive brain reactions to change in auditory stimuli.

MMN and Contrast

Various experiments have shown much stronger MMN to acoustic differences that cross NL phoneme boundaries.

Phillips et al. 2000

MEG investigation of stimuli varying on [tæ-dæ] continuum.

English listeners responded differently when standard/deviant boundary crossed [t-d] phoneme boundary than when it fell within a category, though degree of acoustic variation was the same.

Stronger MMN/MMF with NL contrast

Japanese, French: [ebzo] vs. [ebuzo]

(Dehaene-Lambertz et. al. 2000) Japanese, English: [ra] vs. [la]

(Zhang et. al. 2003) Hungarian, Finnish: [æ] vs. [e]

(Winkler et. al. 1999) Hindi, English: [pa] vs. [ba]

(Sharma and Dorman 2000)

Hwang, Broselow, Squires tested Korean responses to

1. enne vs. ene (possible NL contrast)

[kannan] ‘newborn’ vs. [kanan] ‘poverty’

2. elle vs. ele (not a possible NL contrast,

because *[ele] is illegal)

Supported by NSF grant BCS-07460227

Subjects

10 native speakers of Korean, now students at SUNY Stony Brook, in US 6months – 3 years

All proficient speakers of English

Task

Subjects watched a silent movie.

Subjects heard through headphones:enne – enne - enne- enne- ene – enne…

orelle – elle – elle – elle – ele – elle – elle …

(8 blocks of 300 trials = 2400 trials)onset of deviance: 88ms.

Same acoustic difference

Both the [ene] and [ele] stimuli were created by shortening the duration of the long consonants in [enne], [elle].

Exactly the SAME durational change for[enne] = [elle] 98ms.[ene] = [ele] 48ms.

Same acoustic difference, but different MMN responses (preliminary results)

Change from [enne] to [ene]: Stronger MMN

Change from [elle] to [ele]: Weaker MMN

STRONGER MMN RESPONSE to the cross-category change ([enne] – [ene]) than to the within-category change ([elle]-[ele]).

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*4.avg2.avg Electrode: FZ

Subject: EEG file: 4.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:51:42 17-Apr-2008

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*8.avg6.avg Electrode: FZ

Subject: EEG file: 8.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:50:25 17-Apr-2008

StandardDeviant

ele

ene

Grand Average of responses to Standards and Deviants

• Black line: response to ele after ele,

or ene after ene

• Red line: response to ele after elle,

or ene after enne

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*4.avg2.avg Electrode: FZ

Subject: EEG file: 4.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:51:42 17-Apr-2008

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*8.avg6.avg Electrode: FZ

Subject: EEG file: 8.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:50:25 17-Apr-2008

StandardDeviant

ele

ene

Grand Average of responses to Standards and Deviants

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*2diff.avg4diff.avg Electrode: FZ

Subject: EEG file: 2diff.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:54:21 17-Apr-2008

MMN

Grand Difference Wave (Deviant-Standard)

EleEne

• Shows difference in response to elle-ele change vs. enne-ene change.

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*2diff.avg4diff.avg Electrode: FZ

Subject: EEG file: 2diff.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:54:21 17-Apr-2008

MMN EleEne

Grand Difference Wave (Deviant-Standard)

ms-200.0 -100.0 0.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0

µV 0.0

1.0

2.0

3.0

4.0

5.0

-1.0

-2.0

-3.0

-4.0

-5.0

*2diff.avg4diff.avg Electrode: FZ

Subject: EEG file: 2diff.avg Recorded : 16:05:09 29-Feb-2008Rate - 500 Hz, HPF - 0.1 Hz, LPF - 30 Hz, Notch - 60 Hz

NeuroscanSCAN 4.3Printed : 12:54:21 17-Apr-2008

EleEne

Grand Difference Wave (Deviant-Standard)

250.00 ms

+2.5

+2.2

+1.9

+1.6

+1.3

+0.9

+0.6

+0.3

0

-0.3

-0.6

-0.9

-1.3

-1.6

-1.9

-2.2

-2.5250.00 ms

+2.5

+2.2

+1.9

+1.6

+1.3

+0.9

+0.6

+0.3

0

-0.3

-0.6

-0.9

-1.3

-1.6

-1.9

-2.2

-2.5

250ms

ele ene

Our original question:

Why VrV > VrV, but VlV > VllV?

kʰo:rasɨ ‘chorus’

kʰolla ‘cola’

Inaccurate Perception: Why Korean listeners interpret ‘cola’ as [kolla]

Korean listeners hear laterality of ‘cola’.

This is a stronger cue than durational cue—in Korean, any lateral segment between vowels must be long.

Mishearing in early processing?

ERP data suggests Korean speakers’ brains respond less strongly to the durational difference in [ele] vs. [elle] than in [ene] vs. [enne].

Native Language Neural Commitment Hypothesis (Kuhl 2004).

Implications for Foreign Language Teaching

If students can’t even hear some of the FL contrasts, will perception training help them?

It’s not all bad news

• Dehaene-Lambertz et al. (2000): at later time windows (where conscious processing may be involved), Japanese speakers responded to ebzo-ebuzo contrast more like French speakers .

It’s not all bad news

Tremblay et al. (1997): training DID improve MMN response to non-native contrast.

But problems do persist, at least for some non-native contrasts.

Interim Summary

Formal phonology tells you which production grammar patterns are learnable.

3 unlearnable patterns (in Fijian, Malayalee English, Korean) result from transfer of perception grammar—foreign language acoustic cues are interpreted in terms of NL contrasts.

This misperception seems to occur at early levels of processing, and to persist even after extensive exposure to foreign language.

However, listeners may be able to overcome this at higher levels of processing.