stop place contrasts before liquids edward flemming mit
Post on 21-Dec-2015
216 views
TRANSCRIPT
![Page 1: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/1.jpg)
Stop Place Contrasts before Liquids
Edward Flemming
MIT
![Page 2: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/2.jpg)
Is there a biological grounding of phonology?
• Phonetic/phonological systems are shaped by the need to support rapid, robust communication,
• …given the limits of our speech production/perception apparatus.
• Biology imposes constraints on phonology.• Efficient communication:
– Maximize the distinctiveness of contrasts
– Minimize articulatory effort
– Maximize the rate of information transmission
Auditory, visual systems
Vocal tract, motor control,…
![Page 3: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/3.jpg)
Restrictions on coronal-lateral clusters
• A case study adopting this approach: Stop place contrasts before liquids.
• Many languages allow [pl, kl]/[bl, gl] clusters, but exclude initial [tl, dl] (Kawasaki 1982).• E.g. English, German, Norwegian, Thai, etc
• English: [b-d-g, p-t-k] contrast before [r], brew-drew-grew, pry-try-cry [b-g, p-k] contrast before [l], blue-glue, plan-clan
initial [dl-, tl-] are not possible.
![Page 4: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/4.jpg)
Restrictions on coronal-lateral clusters• This is a result of a dispreference for coronal-dorsal stop
contrasts before laterals (Flemming 1995).
• Some languages reverse the English pattern, [tl-, dl-] OK, but no *[kl-, gl-].
• e.g. Haroi and other Chamic languages (Mudhenk & Goschnick
1977), Katu dialects (Wallace 1969):
• Some languages have free variation between coronal and velar before lateral (but contrast elsewhere), e.g. Bolton English (Shorrocks 1998), Mong Njua (Lyman 1974)
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
![Page 5: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/5.jpg)
Restrictions on coronal-dorsal contrasts before [l]
• Kawasaki (1982) hypothesizes that this dispreference is due to perceptual similarity of [dl-gl], [tl-kl].
• General hypothesis: preferred clusters are those in which all contrasts are perceptually distinct (cf. Ohala 1992, Steriade 1999, Wright 2004, etc). Before [l], contrasts between coronal & dorsal stops are not very
distinct.Evidence:• Kawasaki (1982): Evidence from 1 speaker that formant transitions are
very similar in [dl-, gl-].- But bursts can be sufficient to distinguish stops.
• Hallé, et al (1998), Hallé & Best (2007):- French listeners identify (illegal) [dl-, tl-] as [gl-, kl-] respectively.- French and Am. English listeners have difficulty discriminating
Hebrew [dl-gl] and [tl-kl] contrasts.
![Page 6: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/6.jpg)
Restrictions on coronal-dorsal contrasts before [l]
• Further investigate Kawasaki’s hypothesis through acoustic analysis of American English and Hebrew.
• Would English [dl-gl] and [tl-kl] contrasts be less distinct than stop place contrasts before [r] (and vowels)?
• How do we infer the expected realization of [dl-, tl-]?• Other stop-liquid clusters• Medial [-dl-, -tl-] clusters• [tl-, dl-] in languages that allow these clusters (e.g. Hebrew,
Russian).• But NB languages that allow these contrasts may realize stop-liquid
clusters in a different fashion, e.g. less gestural overlap.
![Page 7: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/7.jpg)
Cues to stop place contrasts
• Prevocalic stops (e.g. Dorman et al 1977):
Release burst - transient + fricationFormant transitions
burstformant transitions
Time (s)26.1405 26.5479
0
5000
![Page 8: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/8.jpg)
Materials
• 6 near-minimal triplets for br-dr-gr• 6 near-minimal pairs for bl-gl• 9 triplets for [b, d, g], each preceding the same set of nine
vowels.
b d g _r brown drown ground _l blow glow _V bid did gig
• Sentence frame ‘Say X to me’• Presented twice in random order• 5 native speakers of American English, 4 female, 1 male.
![Page 9: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/9.jpg)
Quantifying burst shape
• Measured from smoothed spectra (Hanson & Stevens 2003) Calculate a series of seven DFTs on 3 ms windows at 1 ms
intervals. Average these spectra.
![Page 10: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/10.jpg)
Quantifying burst shape
bl bursts
gl bursts
• Burst peak: amplitude peak of the burst spectrum
• Amid-Ahi (cf. Suchato et al 2005)
•Amid = average amplitude from 1.25 kHz - 3 kHz
•Ahi = average amplitude from 3.5 kHz - 8 kHz
mid high
![Page 11: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/11.jpg)
Measurements
Burst:• Burst duration - from stop release to onset of first formant.
• Usually coincides with onset of voicing, but weakly voiced frication is included in the burst.
Formants:• Measured F2 and F3 at the end of the burst, or the onset of formants.
Time (s)58.0934 58.2355
0
5000
58.1442 58.168658.1755
br
![Page 12: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/12.jpg)
Stop-[l] clusters - formants
• Stops are not well differentiated by formant transitions before [l].
Formant onsets
0
500
1000
1500
2000
2500
3000
3500
F2 F3
Hzdlgl
Formant onsets
0
500
1000
1500
2000
2500
3000
3500
F2 F3
Hzblgl
• Initial [bl-, gl-]• No significant differences
in formant onsets.
• Medial [-dl-, -gl-]• Small differences in F2 onsets
• -dl- seems to allow more coarticulatory influence of a preceding front vowel.
![Page 13: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/13.jpg)
Stop-[l] clusters - formants
• Stops are not well differentiated by formant transitions before [l].
• Similar results from a preliminary study of Hebrew initial [bl-, dl-, gl-], [pl-, tl-, kl-] clusters:• F2 and F3 onsets are very close to steady state values
for [l] for all places of articulation.• except F3 is somewhat lower after [b] compared to [d,
g].• Stops appear to be overlapped with following lateral, so
formants are onset are largely determined by [l].• Effect is particularly striking for English [-dl-], since [d] is usually
characterized by relatively high F2 at release.• Possibly lateral release of [d] results in a lower F2 onset.
![Page 14: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/14.jpg)
Stop-l clusters - burst
• [gl] is more compact than [bl].
• [gl] has a longer burst than [bl].
* p < 0.01
frequency of peak
0
500
1000
1500
2000
bl gl
Hz*
burst duration
0
5
10
15
20
25
30
35
bl gl
burst duration (ms)
*
• [gl] burst has a higher frequency peak than [bl] burst.
Amid-Ahi
0
5
10
15
20
bl gl
dB
*
• Initial [bl-, gl-] clusters are distinguished by burst quality and duration.
![Page 15: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/15.jpg)
Stop-l clusters - burst
• Medial [-dl-, -gl-] are also differentiated by their bursts.• But the properties of [-dl-] bursts deviate substantially
from prevocalic [d] bursts in the direction of [g]/[gl] bursts.
burst duration
0
5
10
15
20
25
30
35
dl gl
burst duration (ms)
Amid-Ahi
0
5
10
15
20
dl gl
dB
frequency of peak
0
500
1000
1500
2000
2500
dl gl
Hz
![Page 16: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/16.jpg)
![Page 17: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/17.jpg)
Lateral release
• The properties of the [dl] burst are expected consequences of laterally releasing [d].
• Centrally released [d] burst has significant high frequency energy because it is filtered by the short cavity in front of the alveolar closure.
• But with lateral release, the front cavity includes the side passages opened up by lowering the sides of the tongue, and thus is significantly longer.
• Hence lower frequency peak, more compact burst shape.
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture. Fant 1960
![Page 18: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/18.jpg)
Restrictions on coronal-lateral clusters
• Preliminary study of medial [-dl-,-gl-] in English- difference in formant transitions in some contexts.- difference in burst spectrum (Peak: [dl] 1579 Hz, [gl] 1177 Hz)- but medial [-gl-] is a bit different from initial [gl-]
Time (s)0.276954 0.524867
0
5000
Time (s)0.278185 0.499791
0
5000
(ba)dly (Ba)gleyTime (s)
0.000422777 0.221650
5000
glee
![Page 19: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/19.jpg)
Frequency (Hz)0 8000
–30
40
Frequency (Hz)0 8000
–30
40
Frequency (Hz)0 8000
–30
40
Frequency (Hz)0 8000
–30
40
0 1000 2000 3000 4000 5000 6000 7000 8000
0 1000 2000 3000 4000 5000 6000 7000 8000
Restrictions on coronal-lateral clusters
• Hebrew contrasts initial [bl, dl, gl], [pl, tl, kl].
dl
gl
Time (s)0.140447 0.335739
0
5000
Time (s)0.120813 0.320904
0
5000
![Page 20: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/20.jpg)
Introduction
• A case study adopting this approach: Stop place contrasts before liquids.
Background:• All languages allow stop place contrasts before
vowels.• Many languages permit word-initial stop place
contrasts before liquids. E.g. English: [b-d-g] contrast before [r], brew-drew-grew [b-g] contrast before [l], blue-glue
• In some languages, stop-liquid clusters are the only onset clusters, e.g. Spanish.
![Page 21: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/21.jpg)
Introduction
Structure:• Dispreference for dl-gl• Theory: insufficiently distinct.• Evidence: other stop-l clusters, medial, other lgs, Tr clusters for comparison
(3-way contrast).• Cues to stop place: burst, formant transitions• Measures• What’s wrong with dl-gl?• Tl clusters not differentiated by formants
– English initial, medial, Hebrew initial– compare Tr clusters– Why? coproduction with (velarized) [l] - normal for b, g, not for d
• Tl clusters are differentiated by burst durn, quality– but [dl] bursts are non-canonical, shifted towards velars
• So 3 way contrast would have to be realized by burst - less distinct than pre-r, pre-V.
![Page 22: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/22.jpg)
Introduction
Two questions:• Why are stop-liquid clusters preferred onset
clusters?• Why are [tl-kl], [dl-gl] contrasts dispreferred?Hypotheses:• Preferred clusters are those in which contrasts are
perceptually distinct. • Stop place is generally well-cued before liquids.• But coarticulatory effects render coronal and velar
stops perceptually similar before [l] (Kawasaki 1982).
![Page 23: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/23.jpg)
Introduction
• The preference for stop-liquid clusters is often attributed to a preference for large sonority rise between consonants in an onset.
• Alternative: preferred clusters are those in which all contrasts are perceptually distinct (cf. Ohala 1992, Steriade 1999, Wright 2004, etc)
• High sonority of liquids is relevant only because more sonorous sounds are generally better able to support the realization of cues to adjacent consonants.
• This line of analysis can be extended to account for restrictions that are unrelated to sonority: dispreference for coronal-velar contrasts before laterals.
![Page 24: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/24.jpg)
The present study
• Investigate acoustic properties that could serve as cues to stop place contrasts in stop-liquid clusters, using American English as a case study.
• Many languages permit stop place contrasts before liquids. E.g. English: [b-d-g] contrast before [r], brew-drew-grew [b-g] contrast before [l], blue-glue
initial [dl-] is not possible.
• What is the nature of cues to place in this position? How doe they compare to place cues in prevocalic position?
• Why are liquids good contexts for stop place contrasts?• Why is the pre-[l] context not as good as the prevocalic
context? Specifically, why are [dl-gl]/[tl-kl] contrasts often excluded?
![Page 25: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/25.jpg)
bl(ow)Time (s)0.350678 0.470090
5000
Time (s)0.312515 0.4872220
5000
Time (s)0.322387 0.5226070
5000
Time (s)0.337107 0.5374110
5000
Time (s)0.352544 0.5524270
5000
gl(ow)
br(ew) dr(ew) gr(ew)
![Page 26: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/26.jpg)
br vs. dr vs. gr - Formants
• Formant transitions distinguish [br, dr, gr].
* p < 0.01
Formant onsets
0
500
1000
1500
2000
2500
F2 F3
Hz
brdrgr
* **
![Page 27: Stop Place Contrasts before Liquids Edward Flemming MIT](https://reader038.vdocuments.site/reader038/viewer/2022103123/56649d6a5503460f94a48e55/html5/thumbnails/27.jpg)
br vs. dr vs. gr - burst
• burst distinguishes [br, dr, gr]
* p < 0.05
burst duration
0
0.01
0.02
0.03
0.04
0.05
br dr gr
burst duration (ms)
*
*
frequency of peak
0
500
1000
1500
2000
br dr gr
Hz
* *
*
Amid-Ahi
0
5
10
15
20
br dr gr
dB
*
*