Table Of ContentLenition in the production and perception of
Chilean Spanish approximant consonants:
Implications for lexical access models
Mauricio Alejandro Figueroa Candia
A thesis submitted in fulfilment of requirements for the degree of
Doctor of Philosophy
to
Department of Speech, Hearing and Phonetic Sciences
University College London (UCL), London, UK
2016
Declaration
I, Mauricio Alejandro Figueroa Candia, confirm that the work presented in this
thesis is my own. Where information has been derived from other sources, I confirm
that this has been indicated in the thesis.
Mauricio Alejandro Figueroa Candia
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Abstract
Chilean Spanish approximant consonants [β βð βɣβ] display high degrees of lenition,
which often leads to elision in several phonetic contexts. The fact that these units can
surface at any stage in a continuum from approximant to elided is an ideal testing
ground for exploring how listeners attain lexical access while coping with varying
degrees of acoustic and semantic information, and provides important evidence for
evaluating the predictions that lexical access models make about processing highly
degraded and variable signals.
An initial production study was conducted to determine the scope of lenition for /b d
g/ in Chilean Spanish. Ten native speakers were recorded while completing three
elicitation tasks: word-lists, short texts and semi-guided conversations. Several duration,
intensity and formant measurements were extracted, normalized and analysed. The
results showed that lenition and elided variants are indeed a common feature of these
consonants, and that the relevant variability is encoded in the interaction between
duration, intensity and F1.
Given this variation, the second study investigated how listeners resolve potential
ambiguities in speech processing. Continua from approximant consonant to elision were
prepared and presented to listeners in conditions which varied in the degree of acoustic
and semantic cues available, in several perception tasks: phoneme monitoring,
identification and discrimination. For phoneme monitoring and identification, the results
for /b/ and /d/ showed category boundary shifts when semantic information became
available, but no further semantic priming effects. No significant category boundary
shifts were observed for /g/. The results from the discrimination tasks, on the other
hand, showed that sensitivity to differences between consonant presence and elision
rises as lenition increases.
The results from the production and perception studies are discussed in the light of
lexical access models, in particular with regard to the divide between abstractionist,
episodic and hybrid models.
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Acknowledgements
First and foremost, I want to express my deepest gratitude to my main supervisor,
Bronwen Evans, whose support and encouragement along this process have been
paramount. Her ideas, insight, suggestions and guidance always greatly improved my
research, while at the same time refined my points of view. I also sincerely thank her for
allowing me to collaborate with her in teaching and supervising, all of which I
thoroughly enjoyed.
I am also indebted to other members of the Speech, Hearing and Phonetic Sciences
department, and the Linguistics department. Firstly, thanks to my second supervisor,
John Harris, and to Paul Iverson and Patti Adank, for very useful feedback given to me
during my upgrade. Secondly, thanks to Mark Huckvale and Stuart Rosen for their help
with several methodological issues.
This dissertation was assisted in several ways by Chilean colleagues, to all of whom
I sincerely say gracias. Thanks to Domingo Román for help collecting data for the first
production study; to Camilo Quezada for early advice on statistical analyses; and to
Rosa Catalán, Nicolás Retamal, Josué Pino and Claudia Castro, for assistance collecting
data for perception experiments.
To all the anonymous participants, my deepest gratitude. Your names will be
forgotten –pursuant UK's Data Protection Act 1998–, but your responses will remain
forever plotted.
I had the pleasure to share my postgraduate experience with an amazing group of
fellow-students and post-doctoral seniors. Many thanks first to José Joaquín Atria, Kurt
Steinmetzger (and Natalie), Tim Schoof and Michèle Pettinato, for friendship,
encouragement and for many inspired conversations. Thanks also to Georgina Oliver,
Wafa Alshangiti, Nada Al-Sari and Melanie Pinet, for your friendship and generous help
along my wife's and my own experience in London, and particularly while enduring our
crash-course into parenthood. Thanks also to my dear friends Sonia Granlund, Yasuaki
Shinohara (my Chop-Chop buddy), Alberto Lee, Gisela Tomé and Yasna Pereira.
This dissertation was funded by Becas Chile, from the Chilean Ministry of
Education, via CONICYT. Thanks to all the corresponding bodies and agencies for
financial support during these years.
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Finally, many thanks to my family. First to my parents, Patricia and Dante, for
continuous support. Thanks too to Isabel and Juan Manuel, my in-laws, for visiting us
several times in London and for your help during very challenging months with the
baby. Many thanks, finally, to Paula, compañera de mis días y del porvenir. Thank you
so much for joining me in this rather crazy journey.
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Contents
Declaration ............................................................................................................2
Abstract .................................................................................................................3
Acknowledgements ...............................................................................................4
Contents .................................................................................................................6
List of figures ........................................................................................................10
List of tables ..........................................................................................................13
List of equations ...................................................................................................16
Chapter 1. Summary of chapters ........................................................................17
1.1. Chapter-by-chapter summary ..........................................................................17
Chapter 2. General introduction ........................................................................ 21
2.1. Lenition ...........................................................................................................21
2.2. Cue weighting ................................................................................................. 24
2.3. Phonological recovery and lexical effects on perception ................................26
2.4. Lexical access models .....................................................................................28
2.4.1. Abstractionist models .............................................................................29
2.4.2. Episodic models .....................................................................................34
2.4.3. Hybrid models ........................................................................................36
2.5. Approximant consonants of /b d g/ ..................................................................39
2.5.1. Defining the term 'approximant' .............................................................39
2.5.2. Spanish /b d g/ and their approximant variants ......................................41
2.5.3. Chilean Spanish /b d g/ ...........................................................................44
2.6. The current thesis ............................................................................................48
Chapter 3. Production of /b d g/: Introduction and methods ...........................50
3.1. Introduction .....................................................................................................50
3.1.1. Summary of state of the art ....................................................................50
3.1.2. Methodological standards ......................................................................52
3.2. Aims and objectives .........................................................................................54
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3.3. Data collection .................................................................................................55
3.3.1. Participants .............................................................................................55
3.3.2. Elicitation procedures .............................................................................56
3.3.3. Recordings ..............................................................................................59
3.3.4. Segmentation, labelling and coding .......................................................59
3.3.5. Variables and measurements ..................................................................63
3.4. Normalization procedures ...............................................................................65
3.4.1. Duration ..................................................................................................65
3.4.2. Intensity ..................................................................................................67
3.4.3. Formants .................................................................................................72
Chapter 4. Production of /b d g/: Results, analyses and discussion .................77
4.1. Database overview ..........................................................................................77
4.2. Acoustic properties of approximant variants of /b d g/ ...................................79
4.2.1. Duration ..................................................................................................80
4.2.2. Intensity ..................................................................................................83
4.2.3. Formants (F1, F2) ...................................................................................86
4.3. The role of indexical variables in the production of /b d g/ ............................91
4.3.1. Phonetic context .....................................................................................91
4.3.2. Word status .............................................................................................97
4.3.3. Elicitation procedure ..............................................................................102
4.3.4. Internal word frequency .........................................................................107
4.4. Summary of results ..........................................................................................110
4.4.1. Acoustic properties .................................................................................111
4.4.2. Indexical variables ..................................................................................113
4.5. Discussion .......................................................................................................115
4.5.1. Explaining the variation of Chilean Spanish /b d g/ ...............................115
4.5.2. On methodological standards .................................................................118
4.5.3. Implications for speech perception ........................................................ 120
Chapter 5. Perception of the bilabial–labiodental contrast within /b/ ............ 122
5.1. Introduction .....................................................................................................122
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5.2. Aims ................................................................................................................ 124
5.3. Methods ...........................................................................................................125
5.3.1. Participants .............................................................................................125
5.3.2. Stimuli ....................................................................................................125
5.3.3. Procedure ................................................................................................130
5.4. Results .............................................................................................................133
5.4.1. Identification of natural stimuli ..............................................................133
5.4.2. Identification of synthetic stimuli ..........................................................135
5.4.3. Discrimination ........................................................................................136
5.5. Discussion .......................................................................................................137
Chapter 6. Recovery, lexical effects and lexical access in /b d g/ ..................... 141
6.1. Introduction .....................................................................................................141
6.2. Aims ................................................................................................................144
6.3. Methods ...........................................................................................................145
6.3.1. Participants .............................................................................................145
6.3.2. Stimuli ....................................................................................................145
6.3.3. General procedures .................................................................................154
6.3.4. Procedures for phoneme monitoring ......................................................155
6.3.5. Procedures for identification ..................................................................157
6.3.6. Procedures for discrimination ................................................................158
6.3.7. Summary of procedures .........................................................................160
6.4. Results .............................................................................................................161
6.4.1. Phoneme monitoring ..............................................................................162
6.4.2. Identification ..........................................................................................169
6.4.3. Discrimination ........................................................................................175
6.4.4. Note on statistical analyses ....................................................................183
6.5. Summary of results ..........................................................................................185
6.6. Discussion .......................................................................................................189
6.6.1. Interpreting the results ............................................................................189
6.6.2. Evidence for phonological recovery ...................................................... 197
6.6.3. Agreement with lexical access models ...................................................198
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6.6.4. Some limitations .....................................................................................206
Chapter 7. Follow-up study: Semantic priming in the perception of /b d g/ .. 207
7.1. Introduction .....................................................................................................207
7.2. Methods ...........................................................................................................208
7.2.1. Participants .............................................................................................208
7.2.2. Stimuli ....................................................................................................209
7.2.3. Procedures ..............................................................................................216
7.3. Results .............................................................................................................217
7.4. Discussion .......................................................................................................220
Chapter 8. General discussion .............................................................................224
8.1. Lenition in Chilean Spanish /b d g/: linking production and perception .........224
8.2. Challenges to lexical access models ................................................................228
8.3. Limitations and future research .......................................................................234
8.3.1. Temporal aspects of the word-recognition process ................................234
8.3.2. Acquisition and L2 learning ...................................................................235
8.3.3. The articulatory domain .........................................................................237
8.4. Concluding remarks ........................................................................................238
References .............................................................................................................240
Appendixes ............................................................................................................264
Appendix 1: Full list of continua from Chapter 6 ..................................................264
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List of figures
Figure 3.1 Example of a segmented open approximant consonant from the
word [ˈse.ðeβ ] (sede, “headquarters”). .................................................60
Figure 3.2 Coding example for two tokens of /d/ and /b/. ...................................61
Figure 3.3 Waveform, spectrograms, intensity contours and TextGrids for the
allophonic categories coded for the target segments. .........................62
Figure 3.4 Boxplots comparing raw and normalized duration values, separately
for approximant consonant variants, aggregated for /b d g/. ..............67
Figure 3.5 Schematic representation of maxVel and minVel calculations for
intensity values. ..................................................................................69
Figure 3.6 Kernel density plots for raw intensity measurements and relative
intensity indexes. ................................................................................71
Figure 3.7 Kernel density plots for raw and normalized formant measurements,
shown separately for data from female and male tokens. ...................74
Figure 3.8 Kernel density plots for raw and normalized formant measurements,
shown separately for three phoneme categories. ................................75
Figure 4.1 Boxplots for normalized duration values for three approximant
variants of /b/, /d/ and /g/. ...................................................................81
Figure 4.2 Boxplots for normalized intensity values for three approximant
variants of /b/, /d/ and /g/. ...................................................................85
Figure 4.3 Boxplots for Lobanov-normalized F1 values for three approximant
variants of /b/, /d/ and /g/. ...................................................................87
Figure 4.4 Boxplots for Lobanov-normalized F2 values for three approximant
variants of /b/, /d/ and /g/. ...................................................................90
Figure 4.5 Waveform and spectrogram for the word viendo /ˈbien.do/,
“seeing”. .............................................................................................94
Figure 4.6 Kernel density plots for the 100 most frequent lexical items from
/b/. .......................................................................................................108
Figure 4.7 Kernel density plots for the 100 most frequent lexical items from
/d/. .......................................................................................................109
Figure 4.8 Kernel density plots for the 100 most frequent lexical items from
/g/. .......................................................................................................110
Figure 5.1 Spectrograms and waveforms for four natural nonsense words. ........127
Figure 5.2 Still frames for the points of maximum articulatory constriction in
the approximant consonants for four nonsense words. ......................128
Figure 5.3 Spectrograms, waveforms and formant trajectories for the four
synthetic target stimuli. .......................................................................129
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