Transcript Prosodic Plosives

Prosody – a missing link
between phonetic detail and
phonemic categories?
Claudia Kuzla
Max Planck Institute for Psycholinguistics, Nijmegen
Prosodic Allophones
• 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)
Q:
1 June 2007
How are phonemic contrasts affected
by prosodic conditioning of phonetic detail?
NVFW Seminar on Prosody
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Prosodic Structure
ip
Intermediate Phrase (= ip)
Word (=Wd)
Syllable
higher
IP
Intonational Phrase (= IP)

ip


      
lower
(Beckman & Pierrehumbert 1986)
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Prosody & Phonetic Detail
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
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NVFW Seminar on Prosody
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The ‘Fortition’ Account
• Early articulatory data:
Segments get ‘stronger’ at higher prosodic
boundaries.
• Sound change occurs first in prosodically weak
positions.
Q:
1 June 2007
(Fougeron 1997)
Is a prosodically ‘weak’ [p]
still different from a ‘strong’ [b] ?
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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 languagespecific
(Cho & Jun 2000; Cho & McQueen 2005)
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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…
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Speech Materials
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.’
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Prosodic Boundary Categorization
• Major Phrase: [+ Pause, + BoundaryTone]
• Minor Phrase: [- Pause, + BoundaryTone]
• Prosodic Word:[- Pause, - BoundaryTone]
…supported by preboundary lengthening patterns:
Major > Minor > Word
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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]
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Results: Closure duration
Stop closure duration [ms]
120
100
80
Fortis
60
Lenis
40
20
0
Minor
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Word
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Results: VOT
Wd > Minor > Major
Fortis
/k/ > /t/ > /p/
80
60
Lenis
p
t
40
20
0
Major
Wd = Minor = Major
/g/ > /d/ > /b/
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k
100
Voice Onset Time [ms]
Voice Onset Time [ms]
100
80
60
b
Minor
Word
d
40
g
20
0
Major
Minor
NVFW Seminar on Prosody
Word
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Results: Glottal vibration /b,d,g/
% Glottal Vibration
100
80
60
40
20
0
Major
Minor
Word
Major (3.5 %) < Minor (32.2%) < Word (60.0%)
 Against Feature Enhancement
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Results: Burst Intensity Max /p,t,k/
[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

Effect of PCat for /t/ and /k/ :
/t/: Major < Word
/k/: Major < {Minor = Word}
Against predictions of both
‘Fortition’ and Feature Enhancement
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Summary
Acoustic Cue
Prosodic Effect
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
1 June 2007
Feature
Enhancement
NVFW Seminar on Prosody
Fortition
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Exp 2: Voice Assimilation of Fricatives
Word-initial lenis fricatives /v,z/ may be
devoiced if they follow /t/:
/hAt vEld/ →
[hAtvEld]
‘has
forests’
/hAt fEld/ →
[hAtfEld] ‘has fields’
/hAt zAnt/ → [hAtzAnt] ‘has
*/hAt
sAnt/
sand’
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Predictions
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
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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
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Results: Fricative duration
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Results: Glottal vibration (assimilation)
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Summary
Two important cues to the fortis-lenis distinction
remain balanced across prosodic conditions:
Phrase:
longer duration
less devoicing
Word:
shorter duration -> more lenis /v/
more devoicing -> more fortis /f/
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NVFW Seminar on Prosody
-> more fortis /f/
-> more lenis /v/
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Conclusions
Prosodic 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.
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Thank you…
… and
Mirjam Ernestus
Taehong Cho
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