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?
1 June 2007 NVFW Seminar on Prosody 3
Prosodic Structure
Intonational Phrase (= IP) IP
ip ip Intermediate Phrase (= ip)
Word (=Wd)
Syllable
higher
lower
(Beckman & Pierrehumbert 1986)
1 June 2007 NVFW Seminar on Prosody 4
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
1 June 2007 NVFW Seminar on Prosody 5
• 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] ?
1 June 2007 NVFW Seminar on Prosody 6
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)
1 June 2007 NVFW Seminar on Prosody 7
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…
1 June 2007 NVFW Seminar on Prosody 8
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
1 June 2007 NVFW Seminar on Prosody 9
Prosodic Boundary Categorization
• Major Phrase: [+ Pause, + BoundaryTone]
• Minor Phrase: [- Pause, + BoundaryTone]
• Prosodic Word:[- Pause, - BoundaryTone]
…supported by preboundary lengthening patterns:
Major > Minor > Word
1 June 2007 NVFW Seminar on Prosody 10
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]
1 June 2007 NVFW Seminar on Prosody 11
Results: Closure duration
0
20
40
60
80
100
120
Minor Word
Sto
p c
losu
re d
ura
tio
n [
ms]
Fortis
Lenis
1 June 2007 NVFW Seminar on Prosody 12
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
1 June 2007 NVFW Seminar on Prosody 13
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
1 June 2007 NVFW Seminar on Prosody 14
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
1 June 2007 NVFW Seminar on Prosody 15
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
1 June 2007 NVFW Seminar on Prosody 16
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
1 June 2007 NVFW Seminar on Prosody 17
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
1 June 2007 NVFW Seminar on Prosody 18
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
1 June 2007 NVFW Seminar on Prosody 19
Results: Fricative duration
1 June 2007 NVFW Seminar on Prosody 20
Results: Glottal vibration (assimilation)
1 June 2007 NVFW Seminar on Prosody 21
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/
1 June 2007 NVFW Seminar on Prosody 22
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.
1 June 2007 NVFW Seminar on Prosody 23
Thank you…
… and
Mirjam Ernestus
Taehong Cho