Processing phonetic cues and abstraction of phonological representations in adult nonnative speakers Alia Lancaster and Kira Gor Second Language Acquisition Program, University of Maryland, College Park Annual Meeting of the American Association for Applied Linguistics April 11, 2016
Levels of L2 Phonological Representation
Phonological
Phonetic
Models of L2 Phonology Model Native Language Magnet (Kuhl & Iverson, 1995)
Speech Learning Model (Flege, 1995)
Exemplar types (e.g., Pierrehumbert, 2001)
Level of Representation phonetic allophonic phonological
Direct Map from Acoustic to Phonology (Darcy et al., 2012)
phonological
Feature Based Model
phonological
(Brown, 1998)
Second-Language Linguistic Perception (Mayr & Escudero, 2010) Perceptual Assimilation Model Second Language
phonological phonological
(Best & Tyler, 2007)
Automatic Selective Perception (Strange, 2011)
phonetic
Models of L2 Phonology Model Native Language Magnet (Kuhl & Iverson, 1995)
Speech Learning Model (Flege, 1995)
Exemplar types (e.g., Pierrehumbert, 2001)
Level of Representation phonetic allophonic phonological
Direct Map from Acoustic to Phonology (Darcy et al., 2012)
phonological
Feature Based Model
phonological
(Brown, 1998)
Second-Language Linguistic Perception (Mayr & Escudero, 2010) Perceptual Assimilation Model Second Language
phonological phonological
(Best & Tyler, 2007)
Automatic Selective Perception (Strange, 2011)
phonetic
Outline Background • English and Arabic phonological inventories • 2 theories (PAM-L2, ASP) and their predictions Acoustic Analysis • Use objective measures (acoustic cues) to operationalize the predictions of the ASP Behavioral Experiment • Compare predictions of theories to perceptual abilities of adult second-language (L2) learners and native speakers (NS) Discussion
Bilabial Plosive
b
Nasal
m
Labiodental
Dental Alveolar
Trill
f
Fricative
θ ð ẓ
t d ṭ ḍ n r s z ṣ
Postalveolar
Palatal Velar Uvular
k g
ʃ ʒ
Pharyngeal
q
χ ʁ
Glottal/ Laryngeal
?
ħ ʕ
h
Pharyngeal
Glottal/ Laryngeal
Affricate Approximant
w
l
j
Arabic phoneme inventory Bilabial
Labiodental
Dental
Alveolar
Postalveolar
Palatal Velar Uvular
Plosive
p b
t d
k g
Nasal
m
n
ŋ
Trill
f v
Fricative
θ ð
s z
h
ʧ ʤ
Affricate Approximant
ʃ ʒ
w
English phoneme inventory
l ɹ
j McCarthy, 1994
Automatic Selective Perception (ASP) Model Selective Perception Routine (SPR) – a learned set of relevant phonetic properties that best characterize a segment. Acoustic information via discriminant analyses often predict L2 learners identification of L2 segments better than naïve learner identification (Escudero et al., 2012; Gilichinskaya & Strange, 2010; Strange et al., 2004; Strange et al., 2005).
Greater acoustic difference will lead to greater learner perceptual accuracy. • Predictions (before acoustic analysis): learners will be more accurate in perceiving pharyngeals than uvulars. Strange (2011)
Perceptual Assimilation Model for L2 learners (PAM-L2) Learners assimilate a nonnative phoneme to nearest native phoneme Based on articulatory gestures Types of assimilation for L2 segments voiced pharyngeal /ʕ/, voiceless pharyngeal /ħ/, voiced uvular /ʁ/, and voiceless uvular /χ/: /h/
/a/
/ħ/
/ʕ/
Uncategorized /*/ Uvular
Two Category Pharyngeal
/ʁ/
/χ/ Best & Tyler (2007)
Research Question and Predictions Research question: Does the source of difficulty in perception of nonnative segments for adult L2 speakers stem from nonnativelike representations at the phonetic or phonological level? L2 Phonemes pharyngeal /ħ/-/ʕ/
uvular /χ/-/ʁ/
PAM-L2
two category more accurate
uncategorized more accurate
ASP
phonetically distant more accurate
phonetically similar less accurate
Acoustic Analyses
Method Participants • 10 native speakers of English (4 male) • Mean age 24.1 (SD=8.8)
• 6 native speakers of Arabic (2 female) • Mean age 26.8 (SD=3.4)
Materials • Target phonemes • English: /s/, /z/, /h/ • Arabic: /s/, /z/, /h/, /χ/, /ʁ/, /ħ/, /ʕ/
• Context: syllable initial, medial, and final • Vowels: /u/ • Example: [uzu]
Method: Acoustic variables Consonant • • • • • •
Duration Mean intensity Mean F0 (bark) Mean F1 (bark) Mean F2 (bark) Percent Unvoiced
Vowel(s) • • • • •
Duration Mean intensity Mean F0 (bark) Mean F1 (bark) Mean F2 (bark)
Separate analyses by gender
Results: Within-language linear discriminant analysis (LDA) Percentage correct classifications (averaged across gender) • Arabic • Initial: • Medial: • Final:
• English • Initial: • Medial: • Final:
Results: Within-language linear discriminant analysis (LDA) Percentage correct classifications (averaged across gender) • Arabic • Initial: 89% • Medial: 94.5% • Final: 81%
• English • Initial: 100% • Medial: 100% • Final: 96.5%
Results: Cross-language LDA • Uses weighting of acoustic cues of within-language English LDA. Applies these weights to unlabeled Arabic data • Meant to approximate perception of Arabic phonemes by a native speaker of English
• Outcome of LDA: most common classification • A.k.a., the English phoneme that the model predicted to be closest to the Arabic phoneme based on the acoustic variables.
Results: Cross-language LDA • Outcome of LDA: most common classification • A.k.a., the English phoneme that the model predicted to be closest to the Arabic phoneme based on the acoustic variables.
Context
/χ/ voiceless uvular
/ʁ/ Voiced uvular
/ħ/ voiceless pharyngeal
/ʕ/ voiced pharyngeal
Initial
/s/
/s/
/s/
/h/, /s/
Medial
/s/
/s/
/s/
/s/
Final
/s/
/s/
/s/
/h/
Acoustic Results Summary Analysis: Voiced pharyngeal acoustically approximated by different English phoneme than other target phonemes in initial and final contexts Inference: To an L2 learner of Arabic that is a native speaker of English, pharyngeal phonemes are more acoustically different than uvulars in these contexts L2 Phonemes
pharyngeal /ħ/-/ʕ/
uvular /χ/-/ʁ/
PAM-L2
two category more accurate
uncategorized more accurate
ASP
phonetically distant more accurate in initial and final contexts
phonetically similar less accurate in initial and final contexts
Identification and Discrimination
Method Participants • 12 Arabic native speakers (5 female) • Mean age 25.3 (SD=4.3)
• 21 Arabic L2 learners (16 female) • Mean age 19.8 (SD=1.6) Listening Speaking Self-Rating Self-Rating
Reading Writing Self- Cloze Accuracy Self-Rating Rating (Percentage)
Mean
3.76
3.71
3.76
3.71
35.28
Standard Deviation
1.03
1.31
1.35
1.05
7.55
Method Procedure • Discrimination task (AX) • Control example: [uzu] – [usu] • Pharyngeal example: [uʕu] – [uħu] • Uvular example:[uʁu] – [uχu]
• Identification task • Control example: [uzu] • Pharyngeal example: [uʕu] • Uvular example:[uʁu]
• Cloze test • Language History Questionnaire Materials • Nonce word recordings from a male and female native speaker of Arabic
Analysis: Identification Logistic multilevel models • Dependent Variable: Accuracy • Fixed Effects • Phoneme (/ʕ/,/ħ/, /ʁ/ /χ/,and control) • Context (initial, medial, final)
• Random Effects • Intercepts by Subject
• L2 only model • L2 and Native Speaker (NS) model
Results: L2 Identification Accuracy by Context
control /ʕ/
/ħ/
/ʁ/
/χ/
control /ʕ/
/ħ/
/ʁ/
Phoneme
/χ/
control /ʕ/
/ħ/
/ʁ/
/χ/
Results: L2 Identification Accuracy by Context
control /ʕ/
/ħ/
/ʁ/
/χ/
control /ʕ/
/ħ/
/ʁ/
Phoneme
/χ/
control /ʕ/
/ħ/
/ʁ/
/χ/
Results: Identification Accuracy by Context
control control /ʕ/ /ʕ/ control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
/χ/ /χ/ /ʁ/
control control /ʕ/ /ʕ/ control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
Phoneme
/χ/ /χ/ /ʁ/
control /ʕ/ /ʕ/ control control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
/χ/ /χ/ /ʁ/
Results: Identification Accuracy by Context
control control /ʕ/ /ʕ/ control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
/χ/ /χ/ /ʁ/
control control /ʕ/ /ʕ/ control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
Phoneme
/χ/ /χ/ /ʁ/
control /ʕ/ /ʕ/ control control /ʕ/
/ħ/ /ħ/ /ħ/
/ʁ/ /ʁ/ /χ/
/χ/ /χ/ /ʁ/
Results: L2 Identification Classification Table Final Phoneme
Percentage correct classification rate
Most common misclassification
/ʕ/
89.2
/h/ (4.3%), /ʁ/ (4.3%)
/ħ/
83.3
/h/ (9.7%)
/χ/
83
/ʁ/ (7.8%)
/ʁ/
27.9
/χ/ (57.9%)
/h/
36.9
/ħ/ (51%)
/s/
90.5
/z/ (5.1%)
/z/
95.5
/s/ (1.9%)
Native speakers had a 67.7% correct classification rate for /ʁ/ and 34% of the misclassifications were /χ/
Results Summary: Identification Accuracy • /ʕ/ higher in accuracy than all other phonemes in all contexts for L2 learners • Native speakers close to ceiling • /ʁ/ in final context much lower for both L2 and native speakers
Analysis: Discrimination Linear multilevel models • Dependent Variable: Log D-Prime • Fixed • Pair type (control, pharyngeal, uvular) • Context (initial, medial, final)
• Random Effects • Intercepts by Subject and Item
• L2 only model • L2 and Native Speaker (NS) model
Control: [uzu] – [usu] Pharyngeal: [uʕu] – [uħu] Uvular:[uʁu] – [uχu]
Results: L2 D-Prime Pair Type by Context
Control: [uzu] – [usu] Pharyngeal: [uʕu] – [uħu] Uvular:[uʁu] – [uχu]
Results: D-Prime Pair Type by Context
Control: [uzu] – [usu] Pharyngeal: [uʕu] – [uħu] Uvular:[uʁu] – [uχu]
Discussion Predictions L2 Phonemes pharyngeal /ħ/-/ʕ/
uvular /χ/-/ʁ/
PAM-L2
two category more accurate
uncategorized more accurate
ASP
phonetically distant more accurate in initial and final contexts
phonetically similar less accurate in initial and final contexts
Discussion Summary of findings • Identification task: L2 learners were more accurate on /ʕ/ than other target phonemes • Discrimination task: L2 learners were more sensitive to the difference between pharyngeal phonemes than uvulars in all contexts. • Predictions of ASP generally upheld Limitations • Small sample size • No variation in vowel quality
Discussion • Context matters • ASP does provide framework for differences in context
• Markedness hierarchy for L2 phonological acquisition (Eckman, 2008) • Interlanguage Structural Conformity Hypothesis (Eckman, 1991) • Devoicing in final context
Discussion Learners attended to phonetic information. They can use this bottomup information in L2 category formation. “ accounts based on phonetic, and even acoustic, similarity and overlap between native and nonnative tones are likely to be required, in addition to those based on phonological categories” (Reid, Brunham, Kasisopa, Reilly, Attina, Rattanasone & Best, p. 588)
Future Directions • Developmental trajectory • Lexical influence
Thank you! Questions?
Contact:
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