On tone and syllable structure in Cantonese

Alan C. L. YuUniversity of Chicago

Goals

To reexamine certain claims about the interaction between tone and syllable structure in the literature.

The focus will be on the realization contour tones.

Phonetic approach to contour tone licensing condition– The longer the sonorous portion of the rime,

the more complex a tone can be (Gordon 1999/2001, Zhang 2000).‘[The] tolerance of contour tones on syllables which are inherently less well suited to carrying tonal information implies the tolerance of contour tones on syllables which are better suited to manifesting tone’ (Gordon 2001:447)CVV > CVR > CVO > CV

Cantonese tonal inventory

Tone Examples55 (~53) si ‘poetry’11 (21) si ‘time’25 si ‘to send’13 (23) si ‘market’33 si ‘to try’22 (21) si ‘affairs’

Smooth syllablesCV, CVN, CVVN

Checked syllablesCVO, CVVO

Tone Examples55 sɪk̚ ‘to know’33 sɪk̚ ‘to kiss’22 sɪk̚ ‘to eat’

Why do CV syllables carry rising tones but CVO/CVVO syllables do not? (cf. CVO > CV)

CVO

CVVO

CV CVRCVVR

0

50

100

150

200

250

300

350

Dur

atio

n (m

sec)

Syllable type

CVOCVVOCVCVRCVVR

Gordon demonstrates that the rhyme duration of smooth syllables is significantly longer than that of checked syllables in Cantonese.

An Exception

While contour tones are restricted to phonetically long syllables in Cantonese, they are suspended in certain derived forms…

CV(V)O syllables may carry a rising tone (25) when they undergo a process called Pinjam 變音‘ Changed Tone’.

Level Tone Gloss Rising Tone

Gloss

tsʰɑt33 ‘to brush’ tsʰɑt25 ‘a brush’

pʰɑk33 ‘to bat’ pʰɑk25 ‘a racket’

tsɔk22 ‘to chisel’ tsɔk25 ‘a chisel’

tip11 ‘to pile up’ tip25 ‘a plate’sou33 ‘to sweep’ sou25 ‘a broom’tsʰɔ11 ‘to plow’ tsʰɔ25 ‘a plow’pɔŋ22 ‘to weigh’ pɔŋ25 ‘a scale’tɑn22 ‘to pluck’ tɑn25 ‘a

missile’

Pinjam 變音 in Cantonese

An analysis

Gordon (1999) argues that CVVO syllables may host contour tones in the Pinjam contexts because the constraint MAX[morpheme] is ranked higher than the constraint that licenses contour tones in rimes contained solely of sonorants.

拍 in 拍球 拍 in 球拍pʰɑk33 ‘to strike’ pʰɑk25 ‘a racket’

Problems

No empirical confirmation is available.

Languages vary in their responses to the realization of contour tone in syllables with insufficient tone-bearing ability.

Zhang (2001)

A contour tone encounters a syllable with insufficient tone-bearing ability…

Where does Cantonese fall in this typology?

Contour tone-induced lengthening in Cantonese

A production experiment

Subjects

Six native speakers of Cantonese (three males and three females) currently residing in the US.

Methods Stimuli were monosyllabic Cantonese

words of three different syllable types (i.e. plosive-final, vowel-final, and nasal-final), which were chosen to form (near-)minimal pairs or triplets (i.e. with identical rhyme).

Methods For CVV and CV(V)N syllables, the minimal

triplets consisted of three tone types: lexical low-mid-rising (25), lexical level or falling (22, 33, or 21) and Pinjam-derived low-mid-rising (25).

CVV stimuli

CV(V)N stimuli

Methods For the CVVO syllables, minimal pairs

consisted of two tone versions: level (22 or 33) and derived low-mid-rising (25); no lexical low-mid-rising is available.

Both CVVO and CV(V)N tokens contain some short vowels.

CV(V)O stimuli

Methods The targeted syllables were presented as part of a

disyllabic word phrase to ensure that the appropriate pronunciations were rendered.

Certain pairs of targeted syllables are represented by the same Chinese characters; the semantic and pronunciation differences are only apparent when the character is used in the appropriate context.

掃 sou33 ‘to sweep’ vs. 竹掃 t͡sʊk̚55 sou25 ‘a bamboo broom’

Methods The subjects recited a list of Cantonese target

disyllabic words/phrases in the carrier phrase 我會讀 __ 比你聽 /ŋɔ wui tʊk̚ ___ pɛi nɛi tʰæŋ/ three times.

(2 tones x 1 syllable type (CVVO) + 3 tones x 2 syllables (CVV & CV(V)N)) x 10 tokens x 3 repetitions = 240 tokens

Example stimuli

Tone Token GlossLexical level 33 jy23 kɑp̚33 ‘young pigeon’

乳鴿Derived 25 pɑk̚22 kɑp̚25 ‘white pigeon’

白鴿

Measurements

Turning Point

F0 Peak

Onset to Turning Point Onset to F0 Peak

[fɑn25] ‘powder’

Rhyme duration

Measurements

excursion size – pitch difference (in semitone) between adjacent f0 minimum and maximum in the target syllable;

excursion time – time interval between adjacent f0 minimum and maximum in the target syllable;

excursion speed (=excursion size/excursion time).

Hypotheses Null hypothesis = no difference (i.e. the rhyme

of a CV(V)O syllable remains the same regardless the type of tone it bears.

Phonetic approach to contour tone licensing: – CV(V)O syllables with a derived rising tone are longer

than their level-toned counterparts.– No comparable lengthening should be observed in

CVV or CV(V)N syllables since they are already phonetically long.

Duration analysis

How the presence of a contour tone affects syllable duration

Level vs. Derived Rising

CV(V)O with derived R is significantly longer than CV(V)O with a level tone.

No comparable length difference is found in the other syllable types.

** = p < 0.01

**

Discussion These results show that CVVO syllables under

Pinjam are no exceptions to Gordon’s generalization.

When a CVVO syllable acquires a contour tone, its intrinsic shortness is remedied via the lengthening of the rhyme in Cantonese.

Similar patterns are found in Mitla Zapotec (Briggs 1961), Wuyi Chinese (Fu 1984), Gã (Paster 1999).

Question

While the presence of a contour tone affects the duration of the rhyme, what effect does the shortness of CVVO have on the realization of a contour tone?

Analysis of the f0 contour

How syllable structure affects contour tone realization

The rising contours

Patterns of contour alignment

The f0 peak is reached at approximately 90% point of the rhyme regardless of syllable structure.

Patterns of contour alignment The turning point in

CV(V)O comes significantly earlier than that in CVV syllable.

The difference in turning point alignment between obstruent- and nasal-final syllables did not reach the adjusted level of significance (p = 0.036).

The shape of the contour

Excursion size (the rise) The difference between

the excursion sizes of the vowel- and nasal-final syllables reaches significance.

The differences in excursion size between CV(V)O and CVV and between CV(V)O and CV(V)N did not reach significance. CV(V)O CVV CV(V)N

Syllable type

2.60

2.80

3.00

3.20

3.40

Excu

rsio

n si

ze (i

n se

mito

ne)

** = p < 0.01

**

Excursion time The excursion times for

all three syllables are significantly different from each other.

This suggests that a rising tone in a CV(V)O syllable must cover as large (if not larger) a pitch rise as CVV syllables but in a much shorter amount of time. CV(V)O CVV CV(V)N

Syllable type

80

100

120

140

Excu

rsio

n tim

e (m

s.)

Excursion speed (the slope)

The pitch excursion speed was significantly faster in the CV(V)O syllable than in the nasal-final syllable (p < 0.001) and than in the CVV syllable.

No difference in slope between CVV and CV(V)N is found.

CV(V)O CVV CV(V)NSyllable type

0.0200

0.0250

0.0300

0.0350

Excu

rsio

n sp

eed

Discussion

The results suggest that rising tones are realized significantly differently across syllable structures.

Tonal target undershoots are observed in obstruent-final and vowel-final syllables.

Yet, the nature of the undershoot differs depending on syllable structure.

Onset truncation in CV(V)O

When the syllable is obstruent-final, tonal target undershoot is in the form of onset-truncation.

The beginning of the rise originates from an earlier point relative to the onset of the rhyme and a higher f0 in an obstruent-final syllable than in a nasal-final syllable.

End truncation in CVV When the syllable is vowel-

final, tonal target undershoot results in end-truncation instead.

While the rising tone in both vowel- and nasal-final syllables originate from the same point, the rise in a vowel-final syllable culminates at a lower f0 than observed in a nasal-final syllable.

Discussion

Gordon’s assertion concerning the exception nature of rising tone in CV(V)O is not warranted.

Rhyme duration is lengthened and the rising contour is reduced when an obstruent-final syllable acquires a rising tone from Pinjam.

Puzzle

If contour reduction is possible, then why is lengthening necessary?

Lexical rising tone syllable vs. its level tone counterpart?

Level vs. Lexical Rising CVV and CV(V)N

syllables are longer when their bear a lexical rising tone than when they carry a level tone.

The difference in duration between level and derived rising toned syllables and between lexical and derived rising toned syllables do not reach significance level.

** = p < 0.01

****

Puzzle

Syllables with long rime duration do not necessarily escape the lengthening effect, since CVV and CV(V)N syllables are longer when they bear a lexical rising tone than when they bear a level tone. Why should this be?

Some explanations Many researchers have characterized the observed

differences in syllable duration with respect to the level, extent, and direction of fundamental frequency as physiologically conditioned.

For example, studies on the maximum speed with which pitch can be changed found that subjects were able to perform pitch drops considerably faster than pitch elevation even though the pitch ranges are comparable (Ohala & Ewan, 1973; Sundberg, 1973, 1979; Xu & Sun, 2002).

Perception of tone and duration

Lehiste (1976), for example, found that listeners judge a dynamic (falling-rising or rising-falling), as supposed to a flat f0 pattern, to be longer even when the stimuli are of equal acoustic durations.

– This finding was replicated in other studies on perceived duration of isolated vowels (Pisoni, 1976; Wang, Lehiste, Chuang, & Darnovsky, 1976).

Research question

Does the perceptual effect found in earlier studies on dynamic tone and duration extend to tonal languages?

Methodology

Stimuli A 300 ms [pa] syllable was synthesized using SynthWorks.

A 3-step duration continuum was created with 100 ms. decreasing increments: 300, 200, and 100 ms.

The f0 of the syllable was manipulated to make five stimuli of varying f0 contours.

Name f0 beginning (Hz.) f0 ending (Hz.) average f0 (Hz.)11 85 85 8533 115 115 11555 145 145 14515 85 145 11551 145 85 115

Subjects

Seven native speakers of Cantonese (2 males & 5 females), all students at the University of Chicago, were paid a nominal fee to participate in the experiment.

None of them report any speech or hearing problems.

Procedures Subjects were asked to rate each stimulus for duration on a 7-

point scale, with 1 being the shortest duration and 7 being the longest.

Subjects first completed a practice session of nine trials with the 33 tone stimuli at three durations presented three times in a random order.

After practice, subjects completed an experimental session of 300 trials (5 tones x 3 durations x 20 blocks) with the order of trials randomized within each block.

Procedures The presentation of the stimuli was controlled by the subject.

Presentation of the next item starts after a response is recorded.

The experiment was administered using E‑Prime.

Results

To facilitate cross-subject comparison, the data was first normalized by transforming the rating value to a z‑score

scale.

Discussion

The experimental results suggest that the height and slope of fundamental frequency can significantly affect the listener’s perceived duration of speech sounds.

Discussion

The results w.r.t dynamic f0 are consistent with previous findings.

Dynamic f0 generally lengthens subjective syllable duration.

Discussion

There is an intrinsic perceptual skewing introduced by dynamic f0 movement regardless whether the language is tonal or not.

The contour-tone lengthening effect observed in synchronic typological patterns and diachronic changes may not be purely a matter of physiological constraints on tonal implementation.

Discussion

The fact that lexical rising toned CVV and CV(V)N syllables have longer rhymes than their level toned counterparts may be because rising toned syllables are perceived as longer than level toned syllables.

This perceptual skewing might have been lexicalized as part of the phonetic makeup of rising toned syllables.

Conclusion While duration and sonority are important

factors for contour tone realization, the reverse relationship appears to be equally important.

Duration and sonority might be just as likely to be influenced by tonal movement as contour tone realization may be dependent on duration and sonority.

The End

Results To determine the overall effect of tone and stimulus duration

group upon the listener perceived duration responses, a two-way analysis of variance with TONE and LENGTH as within-subject factors was conducted.

There are significant main effects of stimulus duration and tone but no significant interaction effect is observed.

Source df F Sig.DUR 2 1609.811 .000

TONE 4 21.064 .000DUR * TONE 8 1.358 .210

Because tones had a statistically significant main effect on perceived duration ratings, a post‑hoc analysis, using Bonferroni adjusted alpha levels of 0.01 per test (0.05/5), was conducted for this variable using Student-Newman-Keuls (SNK) tests.

The SNK tests were used because they do not produce overly conservative results when many levels of a single independent variable are compared.

Results

The tones are ordered from the least amount of f0 effect on perceived duration to the most effect.

Zhang (2001) The distribution of contour tones depends on a

phonetic index of the rhyme – Ccontour.

Ccontour is the weighted sum of the sonority and duration of the rhyme (= a · Dur(V) + Dur(R))

The lower the Ccontour value, the more limited the distribution of the contour tones will have on the rhyme.