How does first language influence second language rhythm?

Laurence White and Sven Mattys Experimental Psychology Bristol University

Overview

• Background: Speech rhythm and “rhythm classes”. New speech rhythm metrics.

• Speech production study:Do new rhythm metrics serve to illustrate the influence

of first language on second language rhythm?

• Rhythm (music, speech, etc.) arises from the repetition of related sounds.

• In English speech, rhythm arises from repetition of stressed syllables.

I did not have sexual relations with that woman – Miss Lewinsky.

• In Spanish, there is much less contrast between stressed and unstressed syllables.

A pocos pasos de mi casa está una tienda bonita.

• Traditional distinction: Syllable-timed languages (e.g. Romance). Stress-timed languages (e.g. Germanic).

Background: Rhythm

Stress-timing vs syllable-timing • Stress-timed languages: isochrony?

sleep.ing. soundly vs sleep.il.y. re.searches

• Stress-timing is alternation rather than regularity:

Greater differences between stressed and unstressed syllables… including:

Vowel reduction.

More complex consonant clusters, particularly in stressed syllable onsets and codas.

e.g. (s)(t)(r)a(n)(d)(s)

Fewer open syllables.

Basis of rhythmic analysis

• Separate signal into vocalic and intervocalic sections

and examine variations in length of each.

the standards committee

New rhythm metrics• Variance-based metrics (Ramus, Nespor & Mehler, 1999):

ΔV: standard deviation of vocalic intervals.ΔC: standard deviation of intervocalic intervals.%V: vocalic proportion of total utterance.

Ramus, Nespor & Mehler (1999)

• Also examinedPVI metrics (Low, Grabe & Nolan, 2000;Grabe & Low, 2002).

Overview

• Background: Speech rhythm and “rhythm classes”. New speech rhythm metrics.

• Speech production study:Do new rhythm metrics serve to illustrate the influence

of first language on second language rhythm?

• Comparison between “rhythm classes”:Spanish (“syllable-timed”) vs English (“stress-timed”).

• Six speakers per condition.

• Five sentences per language.

• Other materials also recorded for most speakers:Map task to elicit non-read speech.

Second language recordings

Language spoken

Native language

Spanish English

Spanish

English EngEng

SpEng

EngSp

SpSp

Spanish & English L1/L2 results:

Variance-based metrics

30

35

40

45

50

55

60

65

20 25 30 35 40 45 50 55 60

ΔV

ΔC

8.06.6

5.24.8

Speech rate (syls/sec) EngEngEngSp

SpSp

SpEng

Key Lang. spoken Native lang.

All speakers:Effect of speech rate on ΔV

•VarcoV – ΔV normalised for speech rate: ΔV / Mean V (Dellwo & Wagner, 2003)

3

4

5

6

7

8

9

10

10 20 30 40 50 60 70 80

ΔV

Sp

eech

rat

e (s

ylla

ble

s/se

con

d)

Spanish & English L1/L2 results: Rate normalised ΔV and %V

30

35

40

45

50

55

60

65

70

35 40 45 50 55

%V

Var

coV

EngEng

EngSp

SpSp

SpEng

Key Lang. spoken Native lang.

• A mí no me gustaba su coche pequeño y viejo.

65, 67 vs 67, 66

47, 32 vs 71, 56

40, 41 vs 27, 24

Spanish L1/L2:%V differences continued…

Vowel duration (ms)

SpEng Vowel duration (ms)

SpSp

• What is the effect of speaking a second language, when languages are rhythmically similar?

• Comparison within “rhythm classes”:Dutch (“stress-timed”) vs English (“stress-timed”).

• Six speakers per condition.

• Five sentences per language.

Language spoken

Native language

Dutch English

Dutch

English

Second language recordings

EngEng

DutEng

EngDut

DutDut

35

45

55

65

75

30 35 40 45 50 55

%V

Var

coV

Cross-linguistic results: Dutch vs English

EngEng

EngSp

SpSp

SpEng

Key Lang. spoken Native lang.

DutEng

EngDut

DutDut

First and second language rhythm: summary

• Influence of L1 on L2: Consonantal metrics show little influence of L1. Vocalic metrics:

Normalisation for speech rate necessary (VarcoV). Clearly show influence of L1 on L2.But…

Not necessarily intermediate between L1 and L2.Little accommodation to L2 when languages are

rhythmically similar.

Interpretation of rhythm metrics

• Rhythmic distinctions can be seen as arising from specific segmental and prosodic processes:Rhythm as emergent property rather than product of

top-down timing control.

• Variation within “rhythm classes” sometimes as large as between. Suggests distinction is not simply bimodal.

• Further research: How do rhythm metrics relate to the subjective experience of linguistic rhythm?

Credits

Biotechnology and Biological Sciences Research Council, U.K.

Juan Toro, Barcelona.Elizabeth Johnson, Nijmegen. Eric-Jan Wagenmakers & Atie Vogelenzang de Jong, Amsterdam.Ineke Mennen, Edinburgh. Reinier Salverda, London.