Project 4

Oliver NiebuhrUniversity of KielMeghan ClayardsMcGill University, Montreal

April 5, 2011

Project 4• Research subject of P4 was assimilation of place of articulation…• …contrastively investigated for English and French.

• Involved Institutions: York, Aix, Geneva.• People: Meghan Clayards, Oliver Niebuhr, Gareth Gaskell, Christine

Meunier, Noel Nguyen, Uli Frauenfelder, Leonardo Lancia, Sophie Dufour.

• 2 Steps:– (1) Identification of the PD of place assimilation in E … and F?– (2) Cross-linguistic comparison of the listeners’ sensitivity/ability to use

these details in the decoding of words.

Project 4 Part I• Why place assimilation and why French and English?• Perception-oriented step (2) was the actual starting point.

– French and English are supposed to differ clearly in terms of place assimilation.

– English is well known for having regressive place assimilation across word boundaries (e.g., “swis{s/h} shop”, “ba{d/g} girl”)

– Place assimilation is claimed to not occur in French at all.– So, what do French listeners do with potential instances of place

assimilation, and does it make a difference whether assimilation is partial is complete?

– Ultimately: What kind of cognitive strategy do listeners use in coping with assimilations?

• Is there is single mechanism? • Is it language-specific or language-universal?

Project 4 Part I• Two parallel acoustic analyses of single-sentence read-speech

corpora of 4 English and 4 French speakers.• Elicited with a fast speaking rate similar to the spontaneous

speech of the individual speakers.

• Based on place assimilation in sibilant sequences (/s/, //, /z/, //) across word boundaries…

• …and additional reference sequences of sibilants and labial consonants across word boundaries.

• Acoustic analyses included:– Durations of reference sibilants and sibilant sequences.– Centre-of-gravity (1,5-12kHz) means and ranges of each sibilant and

sibilant sequence.

Project 4 Part I• Main result: English and French are more similar than

commonly thought!– Like English, French does show place assimilation in sibilant

sequences.– Like English, the French assimilations are overall gradual, ranging from

non-assimilations to (temporally & spectrally) complete assimilations.

– But the English assimilation is direction-guided strictly regressive (in some cases /s/ [ss], e.g., “British sea”).

– French assimilation is quality-guided towards post-alveolar into either direction, regressive and progressive.

• Regressive assimilation is stronger, but still less consistent than in English.

• French assimilation occurs independently of simultaneous voice assimilation, which can go into the opposite direction.

Project 4 Part I• Results of duration measurements:

= sibilants in a sequence have equal durations

French: If there are two separable sibilantsections in a sequence, then the postalv.section is almost always clearly longer.

English: There are less sequences withseparable sibilant sections; but if they areseparable, the second sibilant is longer,i.e. no order effect like in French.

Project 4 Part I• Results of centre-of-gravity measurements:

French: single av. and pav. sibilantsclearly differ in mean CoG, both av-pav and pav-av sequences overlap more orless strongly with the pav. reference

English: single av. and pav. sibilantsclearly differ in mean CoG, av-pavsequences are almost all identical withCoGs of pav. reference pav-av differfrom pav. and av. in both CoG means and ranges.

Project 4 part II

• Perception experiments– Phonetic context can radically change

pronunciation – how does the listener recognize “dresh” as

“dress” in “dresh shop”?– At what level is the problem solved?

• Crosses word boundaries so can’t be purely lexical• does it require top-down knowledge?

Visual context

9http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html

Visual context

10http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html

Accounts

Contrast enhancement

• low level• increases dissimilarity

Phonological Inference

11

• language dependant

• high level• ‘undo’ learned patterns

• works on partial assimilation

• not language dependant

• works on partial and complete

Perception Experiment

• Compare languages that differ in assimilation patterns

• Equate stimuli and control acoustics for two language groups- Artificial lexicon

• Use a range of assimilation strengths- Continuum

• Examine the time course of compensation

12

Task

13

25 English listeners (York, UK)

26 French listeners (Geneva, Switzerland)

Rendez le cavisse

pagune s’il vous plait

Render the cavees

pagoon please pagoon

cavees

Task

14

25 English listeners (York, UK)

26 French listeners (Geneva, Switzerland)

pagoon

Rendez le cavisse

pagune s’il vous plait

Render the cavees

pagoon please

cavees

Word 1 Word 2sival

cavees shinnowcaveesh pagoon

pentuf

Word 1 Word 2pidas

tamash samalnalip shamal

remop

Task from Pirog Revill et. al 2008

Word 1 = objects Word 2 = textures

Materials

15

Predictions

Contrast Enhancement Phonological Inference

16

English French

Right context Yes Yes

Left context Yes Yes

English French

Right context Yes ?

Left context no ?

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0 1 2 3 4 5 6 7 8

English listeners

17“sh” “s”

sshcontrol

Left Context

“Render the ...amal”controltamashpidas

/ʃ/1234567

/s/

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0 1 2 3 4 5 6 7 8

French listeners

18

Left context

“sh” “s”

sshcontrol

“Render the ...amal”controltamashpidas

/ʃ/1234567

/s/

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00

Right context

English listeners

19“sh” “s”

sshcontrol

“Render the cavee...controlshinnow”sival”

/ʃ/1234567

/s/

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00

“sh” “s”

sshcontrol

French listeners

20

Right context

“Render the cavee...controlshinnow”sival”

/ʃ/1234567

/s/

Summary

Contrast Enhancement Phonological Inference

21

English French

Right context Yes Yes

Left context Yes Yes

English French

Right context Yes ?

Left context no ?

Eye-movements

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• If compensation is an auditory process, it should happen quickly

• Does it?

Eye-movements

“cavees”“caveesh”“pagoon”

200 ms

12345

Trials

…cavees pagoon…

Time

/s/

- /sh

/ 1

-1

0

Time

% fi

xatio

ns

1

0

Eye-movements

24

Co

ron

al b

ias

(lo

oks

to

/s/

- lo

oks

to

/ʃ/)

Average RT

Render the cavee…

Looks to button start

1

7

cavees

caveesh

Occulo-motor delay (200 msec)

Eye-movements

25

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00

Eye-movements

26

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0 1 2 3 4 5 6 7 8

Summary

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• Compensation for complete assimilation requires language specific experience

• Some other language general mechanism may also be at play for moderate assimilation

• Doesn’t seem to be rapid but might require some top down knowledge as well

Thanks to...

Sound to Sense:

Uli Frauenfelder, Université de Genève

Sarah Hawkins, Cambridge University

Christine Meunier, Université de Provence

Noel Nguyen, Université de Provence

Eyetrackers:

Gerry Altmann, University of York

Dirk Kerzel, Université de Genève

Gareth Gaskell, University of York

Oliver Niebuhr, University of Kiel

Modeling Predictions

Contrast Enhancement

CoG (Hz)“sh”

Prop

ortio

n “s

” re

spon

se

“s”29

Modeling Predictions

Phonological Inference

CoG (Hz) “s”“sh”

Prop

ortio

n “s

” re

spon

se

30