Claudia Kuzla

Max Planck Institute for Psycholinguistics, Nijmegen

Claudia Kuzla

Prosody – a missing link between phonetic detail and

phonemic categories?

1 June 2007 NVFW Seminar on Prosody 2

• Prosody influences phonetic detail:In prosodically prominent positions, speech sounds are articulated more strongly (e.g., Keating et al. 2003)

• Prosodic Phonology: Phonological processes occur within prosodic

domains, but not across prosodic boundaries (Nespor & Vogel 1986)

Prosodic Allophones

Q : How are phonemic contrasts affected by prosodic conditioning of phonetic detail?

Q : How are phonemic contrasts affected by prosodic conditioning of phonetic detail?


Prosodic Structure

Intonational Phrase (= IP) IP

ip ip Intermediate Phrase (= ip)

Word (=Wd)

Syllable

higher

lower

(Beckman & Pierrehumbert 1986)


Articulatory & Acoustic Studies:

“Domain-initial strengthening”

Segments at the beginning of higher prosodic domains are temporally and spatially expanded:

• Longer closure durations• More linguo-palatal contact• Longer Voice Onset Time• Less coarticulation • Less assimilation

Prosody & Phonetic Detail


• Early articulatory data:

Segments get ‘stronger’ at higher prosodic boundaries.

• Sound change occurs first in prosodically weak

positions. (Fougeron 1997)

The ‘Fortition’ Account

Q: Is a prosodically ‘weak’ [p] still different from a ‘strong’ [b] ?

Q: Is a prosodically ‘weak’ [p] still different from a ‘strong’ [b] ?


The Feature Enhancement Account

English: Longer VOT at higher boundaries for all plosives

Dutch: Shorter VOT at higher boundaries for voiceless plosives; more prevoicing for voiced plosives

Enhancement of the features[+ spread glottis] (Engl.) vs. [-spread glottis] (Dutch)

Implementation of Prosodic Strengthening is language-specific

(Cho & Jun 2000; Cho & McQueen 2005)


Exp 1: German Plosives

• /b,p/ : Backen ‘bake’ – Packen ‘pack’

• /d,t/ : Dank ‘thanks’– Tank ‘tank’

• /g,k/: Garten ‘garden’ – Karten ‘cards’

…in sentence contexts, with various prosodic realizations…


Am Samstag wollen wir backen und einkaufen.

‘On Saturday, we want to do baking and shopping.’

Geplant hatten wir, Backen und Einkauf zuerst zu machen.

‘Our plan was to do baking and shopping first.’

Einkaufen müssen wir, backen für morgen, und aufräumen.

‘We have to go shopping, bake for tomorrow, and tidy up.’

Heute segeln wir. Backen kann Anna.

‘Today we go sailing. Baking can be done by Anna.’

Speech Materials


Prosodic Boundary Categorization

• Major Phrase: [+ Pause, + BoundaryTone]

• Minor Phrase: [- Pause, + BoundaryTone]

• Prosodic Word:[- Pause, - BoundaryTone]

…supported by preboundary lengthening patterns:

Major > Minor > Word


Acoustic Measurements

• Closure duration [ms]

• Voice Onset Time [ms]

• Glottal Vibration in /b,d,g/ [% of closure]

• Burst Intensity Maximum for /p,t,k/ [dB]


Results: Closure duration

0

20

40

60

80

100

120

Minor Word

Sto

p c

losu

re d

ura

tio

n [

ms]

Fortis

Lenis


Results: VOT

Lenis

0

20

40

60

80

100

Major Minor Word

Vo

ice

On

set

Tim

e [m

s]

b

d

g

Wd = Minor = Major

/g/ > /d/ > /b/

Wd > Minor > Major

/k/ > /t/ > /p/Fortis

0

20

40

60

80

100

Major Minor Word

Vo

ice

On

set

Tim

e [m

s]

p

t

k


Results: Glottal vibration /b,d,g/

Major (3.5 %) < Minor (32.2%) < Word (60.0%)

Against Feature Enhancement

0

20

40

60

80

100

Major Minor Word

% G

lott

al V

ibra

tio

n


Results: Burst Intensity Max /p,t,k/

Effect of PCat for /t/ and /k/ :

/t/: Major < Word

/k/: Major < {Minor = Word}

[dB] /p/ /t/ /k/

Major 55.09 58.37 59.65

Minor 53.69 58.38 60.58

Word 54.22 59.18 61.53

Against predictions of both

‘Fortition’ and Feature Enhancement


Summary

Acoustic Cue Prosodic Effect Feature Enhancement

Fortition

Closure longer closures at higher boundaries

VOT shorter VOT for /p,t,k/ at higher boundaries

Glottal Vibration

less at higher boundaries

Burst Intensity If any: lower at higher boundaries


Word-initial lenis fricatives /v,z/ may be devoiced if they follow /t/:

// → [] ‘has forests’

// → [] ‘has sand’

// → [] ‘has fields’

*//

Exp 2: Voice Assimilation of Fricatives


Contrast between /v, z/ and /f, s/ is not only cued by glottal vibration, but also by duration.

Prosodic structure might influence exactly these two cues:

- glottal vibration, due to effects on assimilation : more assimilatory devoicing across smaller boundaries

- duration, due to initial strengthening: longer duration after larger boundaries

Predictions


Speech Materials• /f,v,z/ in word-initial position:

[f]elder ‘fields’ , [v]älder ‘forests’ , [z]enken ‘hollows’

• Preceding context :

// in hatte ‘had’ (non-assimilation context),

/t/ in hat ‘has’ (assimilation context)

• Similar sentence sets as in Experiment 1:

Anna hatte Felder und Wiesen gemalt.

…Anna gemalt hat. Felder und Wiesen…

• Same prosodic categorization


Results: Fricative duration


Results: Glottal vibration (assimilation)


Summary

Two important cues to the fortis-lenis distinction

remain balanced across prosodic conditions:

Phrase: longer duration -> more fortis /f/ less devoicing -> more lenis /v/

Word: shorter duration -> more lenis /v/ more devoicing -> more fortis /f/


ConclusionsProsodic structure interacts with phonetic

detail and phonemic categories in a complex way:

• Neither general ‘Fortition’ nor ‘Feature Enhancement’ through the Prosodic Hierarchy;

• Phonological contrasts are phonetically implemented in different ways for different prosodic positions.


Thank you…

… and

Mirjam Ernestus

Taehong Cho

Claudia Kuzla

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