This study investigated the effects of hearing loss and hearing experience on the acoustic features of infant-directed speech (IDS) to infants with hearing loss (HL) compared to controls with normal hearing (NH) matched by either chronological or hearing age (experiment 1) and across development in infants with hearing loss as well as the relation between IDS features and infants' developing lexical abilities (experiment 2). Both experiments included detailed acoustic analyses of mothers' productions of the three corner vowels /a, i, u/ and utterance-level pitch in IDS and in adult-directed speech. Experiment 1 demonstrated that IDS to infants with HL was acoustically more variable than IDS to hearing-age matched infants with NH. Experiment 2 yielded no changes in IDS features over development; however, the results did show a positive relationship between formant distances in mothers' speech and infants' concurrent receptive vocabulary size, as well as between vowel hyperarticulation and infants' expressive vocabulary. These findings suggest that despite infants' HL and thus diminished access to speech input, infants with HL are exposed to IDS with generally similar acoustic qualities as are infants with NH. However, some differences persist, indicating that infants with HL might receive less intelligible speech.
References
1.
Adriaans
, F.
, and Swingley
, D.
(2017
). “Prosodic exaggeration within infant-directed speech: Consequences for vowel learnability
,” J. Acoust. Soc. Am.
141
(5
), 3070
–3078
.2.
Andruski
, J. E.
, and Kuhl
, P. K.
(1996
). “The acoustic structure of vowels in mothers' speech to infants and adults
,” in Proceedings of Fourth International Conference on Spoken Language Processing ICSLP'96
, October 3-6, Vol. 3, pp. 1545
–1548
.3.
Audibert
, N.
, and Falk
, S.
(2018
). “Vowel space and f0 characteristics of infant-directed singing and speech
,” in Proceedings of the 19th International Conference on Speech Prosody
, June 13–16, pp. 153
–157
.4.
Bates
, D.
, Machler
, M.
, and Dai
B.
(2011
). Ime4: Linear mixed-effects models using S4 classes
, R Package Version 0.999375-33
.5.
Benasich
, A. A.
, and Tallal
, P.
(2002
). “Infant discrimination of rapid auditory cues predicts later language impairment
,” Behav. Brain Res.
136
(1
), 31
–49
.6.
Benders
, T.
(2013
). “Mommy is only happy! Dutch mothers' realisation of speech sounds in infant-directed speech expresses emotion, not didactic intent
,” Infant Behav. Dev.
36
(4
), 847
–862
.7.
Bergeson
, T. R.
, Miller
, R. J.
, and McCune
, K.
(2006
). “Mothers' speech to hearing-impaired infants and children with cochlear implants
,” Infancy
10
(3
), 221
–240
.8.
Bernstein Ratner
, N.
(1984
). “Patterns of vowel modification in mother–child speech
,” J. Child Lang.
11
(3
), 557
–578
.9.
Bernstein Ratner
, N.
, and Pye
, C.
(1984
). “Higher pitch in BT is not universal: Acoustic evidence from Quiche Mayan
,” J. Child Lang.
11
(3
), 515
–522
.10.
Bloom
, L.
(1973
). One Word at a Time: The Use of Single-Word Utterances Before Syntax
(Mouton
, the Hague
).11.
Boersma
, P. P. G.
, and Weenink
, D. J. M.
(1996
). Praat: Doing Phonetics by Computer: Version 3.4
(Instituut voor Fonetische Wetenschappen
, Amsterdam, the
Netherlands
).12.
Boons
, T.
, Brokx
, J. P.
, Frijns
, J. H.
, Peeraer
, L.
, Philips
, B.
, Vermeulen
, A.
, and Van Wieringen
, A.
(2012
). “Effect of pediatric bilateral cochlear implantation on language development
,” Arch. Ped. Adolesc. Med.
166
(1
), 28
–34
.13.
Bradlow
, A. R.
, Torretta
, G. M.
, and Pisoni
, D. B.
(1996
). “Intelligibility of normal speech I: Global and fine-grained acoustic-phonetic talker characteristics
,” Speech Commun.
20
(3–4
), 255
–272
.14.
Burnham
, D.
, Joeffry
, S.
, and Rice
, L.
(2010
). “Computer-and human-directed speech before and after correction
,” in Proceedings of the 13th Australasian International Conference on Speech Science and Technology
, December 14–16, Melbourne, Australia, pp. 13–17.15.
Burnham
, D.
, Kitamura
, C.
, and Vollmer-Conna
, U.
(2002
). “What's new, pussycat? On talking to babies and animals
,” Science
296
(5572
), 1435
–1435
.16.
Burnham
, E. B.
, Wieland
, E. A.
, Kondaurova
, M. V.
, McAuley
, J. D.
, Bergeson
, T. R.
, and Dilley
, L. C.
(2015
). “Phonetic modification of vowel space in storybook speech to infants up to 2 years of age
,” J. Speech Lang. Hear. Res.
58
(2
), 241
–253
.17.
Castellanos
, A.
, Benedí
, J. M.
, and Casacuberta
, F.
(1996
). “An analysis of general acoustic-phonetic features for Spanish speech produced with the Lombard effect
,” Speech Commun.
20
(1–2
), 23
–35
.18.
Chong
, S. C. F.
, Werker
, J. F.
, Russell
, J. A.
, and Carroll
, J. M.
(2003
). “Three facial expressions mothers direct to their infants
,” Infant Child Dev. Int. J. Res. Pract.
12
(3
), 211
–232
.19.
Cooper
, R. P.
, and Aslin
, R. N.
(1990
). “Preference for infant-directed speech in the first month after birth
,” Child Dev.
61
(5
), 1584
–1595
.20.
Cristia
, A.
, and Seidl
, A.
(2014
). “The hyperarticulation hypothesis of infant-directed speech
,” J. Child Lang.
41
(4
), 913
–934
.21.
Dodane
, C.
, and Al-Tamimi
, J.
(2007
). “An acoustic comparison of vowel systems in adult-directed-speech and child-directed speech: Evidence from French, English and Japanese
,” in Proceedings of the 16th International Congress of Phonetics Sciences, Saarbrücken, Germany
, pp. 6
–10
.22.
Eaves
, B. S.
Jr, Feldman
, N. H.
, Girffiths
, T. L.
, and Shafto
, P.
(2016
). “Infant-directed speech is consistent with teaching
,” Psychol. Rev.
123
(6
), 758
–771
.23.
Eisenberg
, L. S.
, Martinez
, A. S.
, and Boothroyd
, A.
(2004
). “Perception of phonetic contrasts in infants: Development of the VRASPAC
,” in International Congress Series
, Vol. 1273
(Elsevier
, Amsterdam, the Netherlands)
, pp. 364
–367
.24.
Englund
, K. T.
(2018
). “Hypoarticulation in infant-directed speech
,” Appl. Psycholinguist.
39
(1
), 67
–87
.25.
Englund
, K. T.
, and Behne
, D. M.
(2005
). “Infant directed speech in natural interaction—Norwegian vowel quantity and quality
,” J. Psycholing. Res.
34
(3
), 259
–280
.26.
Fenson
, L.
, Dale
, P.
, Reznick
, J. S.
, Thal
, D.
, Bates
, E.
, Hartung
, J.
, and Reilly
, J.
(1993
). MacArthur Communicative Inventories: User's Guide and Technical Manual
(San Diego
, CA
).27.
Ferguson
, S. H.
, and Kewley-Port
, D.
(2002
). “Vowel intelligibility in clear and conversational speech for normal-hearing and hearing-impaired listeners
,” J. Acoust. Soc. Am.
112
(1
), 259
–271
.28.
Ferguson
, S. H.
, and Kewley-Port
, D.
(2007
). “Talker differences in clear and conversational speech: Acoustic characteristics of vowels
,” J. Speech Lang. Hear. Res.
50
(5
), 1241
–1255
.29.
Fernald
, A.
(2000
). “Speech to infants as hyperspeech: Knowledge-driven processes in early word recognition
,” Phonetica
57
(2–4
), 242
–254
.30.
Fernald
, A.
, Perfors
, A.
, and Marchman
, V. A.
(2006
). “Picking up speed in understanding: Speech processing efficiency and vocabulary growth across the 2nd year
,” Dev. Psychol.
42
(1
), 98
–116
.31.
Fernald
, A.
, and Simon
, T.
(1984
). “Expanded intonation contours in mothers' speech to newborns
,” Dev. Psychol.
20
, 104
–113
.32.
Fernald
, A.
, Taeschner
, T.
, Dunn
, J.
, Papousek
, M.
, de Boysson-Bardies
, B.
, and Fukui
, I.
(1989
). “A cross-language study of prosodic modifications in mothers' and fathers' speech to preverbal infants
,” J. Child Lang.
16
(3
), 477
–501
.33.
Fitzpatrick
, E. M.
, Gaboury
, I.
, Durieux-Smith
, A.
, Coyle
, D.
, Whittingham
, J.
, and Nassrallah
, F.
(2019
). “Auditory and language outcomes in children with unilateral hearing loss
,” Hear. Res.
372
, 42
–51
.34.
Fitzpatrick
, E.
, Grandpierre
, V.
, Durieux-Smith
, A.
, Gaboury
, I.
, Coyle
, D.
, Na
, E.
, and Sallam
, N.
(2015
). “Children with mild bilateral and unilateral hearing loss: Parents' reflections on experiences and outcomes
,” J. Deaf Stud. Deaf Educat.
21
(1
), 34
–43
.35.
Fitzpatrick
, E. M.
, Whittingham
, J.
, and Durieux-Smith
, A.
(2014
). “Mild bilateral and unilateral hearing loss in childhood: A 20-year view of hearing characteristics, and audiologic practices before and after newborn hearing screening
,” Ear Hear.
35
(1
), 10
–18
.36.
Galle
, M. E.
, Apfelbaum
, K. S.
, and McMurray
, B.
(2015
). “The role of single talker acoustic variation in early word learning
,” Language Learning and Development
11
(1
), 66
–79
.37.
Gerstman
, L.
(1968
). “Classification of self-normalized vowels
,” IEEE Trans. on Audio and Electroacoustics
16
(1
), 78
–80
.38.
Graf Estes
, K.
, and Hurley
, K.
(2013
). “Infant-directed prosody helps infants map sounds to meanings
,” Infancy
18
(5
), 797
–824
.39.
Grieser
, D. L.
, and Khul
, P. K.
(1998
). “Maternal speech to infants in a tonal language: Support for universal prosodic features in motherese
,” Dev. Psychol.
24
(1
), 14
–20
.40.
Hartman
, K. M.
, Bernstein Ratner
, N.
, and Newman
, R. S.
(2017
). “Infant-directed speech (IDS) vowel clarity and child language outcomes
,” J. Child Lang.
44
(5
), 1140
–1162
.41.
Hayashi
, A.
, Tamekawa
, Y.
, and Kiritani
, S.
(2001
). “Developmental change in auditory preferences for speech stimuli in Japanese infants
,” J. Speech Lang. Hear. Res.
44
(6
), 1189
–2000
.42.
Hazan
, V.
, and Baker
, R.
(2011
). “Acoustic-phonetic characteristics of speech produced with communicative intent to counter adverse listening conditions
,” J. Acoust. Soc. Am.
130
(4
), 2139
–2152
.43.
Houston
, D. M.
, Pisoni
, D. B.
, Kirk
, K. I.
, Ying
, E. A.
, and Miyamoto
, R. T.
(2003
). “Speech perception skills of deaf infants following cochlear implantation: A first report
,” Int. J. Pediatr. Otorhinolaryngol.
67
(5
), 479
–495
.44.
Houston
, D. M.
, Ying
, E. A.
, Pisoni
, D. B.
, and Kirk
, K. I.
(2001
). “Development of pre-word-learning skills in infants with cochlear implants
,” Volta Rev.
103
(4
), 303
–306
.45.
Jarosz
, A. F.
, and Wiley
, J.
(2014
). “What are the odds? A practical guide to computing and reporting Bayes factors
,” J. Problem Solv.
7
(1
), 2
.46.
47.
Johnston
, J. C.
, Durieux-Smith
, A.
, Angus
, D.
, O'Connor
, A.
, and Fitzpatrick
, E.
(2009
). “Bilateral paediatric cochlear implants: A critical review
,” Int. J. Audiol.
48
(9
), 601
–617
.48.
Joint Committee on Infant Hearing
(2007
). “Year 2007 position statement: Principles and guidelines for early hearing detection and intervention programs
,” Pediatrics
120
(4
), 898
–921
.49.
Kalashnikova
, M.
, and Burnham
, D.
(2018
). “Infant-directed speech from seven to nineteen months has similar acoustic properties but different functions
,” J. Child Lang.
45
, 1035
–1053
.50.
Kalashnikova
, M.
, Carignan
, C.
, and Burnham
, D.
(2017
). “The origins of babytalk: Smiling, teaching or social convergence?
,” R. Soc. Open Sci.
4
(8
), 170306
.51.
Kalashnikova
, M.
, Goswami
, U.
, and Burnham
, D.
(2018
). “Mothers speak differently to infants at-risk for dyslexia
,” Dev. Sci.
21
(1
), e12487
.52.
Kalashnikova
, M.
, Goswami
, U.
, and Burnham
, D.
(2020
). “Infant-directed speech to infants at risk for dyslexia: A novel cross-dyad design
,” Infancy
25
(3
), 286
–303
.53.
Kalashnikova
, M.
, Schwarz
, I. C.
, and Burnham
, D.
(2016
). “OZI: Australian English communicative development inventory
,” First Lang.
36
(4
), 407
–427
.54.
Kitamura
, C.
, and Burnham
, D.
(2003
). “Pitch and communicative intent in mother's speech: Adjustments for age and sex in the first year
,” Infancy
4
(1
), 85
–110
.55.
Kitamura
, C.
, Thanavishuth
, C.
, Burnham
, D.
, and Luksaneeyanawin
, S.
(2001
). “Universality and specificity in infant-directed speech: Pitch modifications as a function of infant age and sex in a tonal and non-tonal language
,” Infant Behav. Dev.
24
(4
), 372
–392
.56.
Knoll
, M.
, and Uther
, M.
(2004
). “Motherese and Chinese: Evidence of acoustic changes in speech directed at infants and foreigners
,” J. Acoust. Soc. Am.
116
(4
), 2522
.57.
Koester
, L. S.
(1995
). “Face-to-face interactions between hearing mothers and their deaf or hearing infants
,” Infant Behav. Dev.
18
(2
), 145
–153
.58.
Kondaurova
, M. V.
, and Bergeson
, T. R.
(2011
). “The effects of age and infant hearing status on maternal use of prosodic cues for clause boundaries in speech
,” J. Speech Lang. Hear. Res.
54
(3
), 740
–754
.59.
Kondaurova
, M. V.
, Bergeson
, T. R.
, and Dilley
, L. C.
(2012
). “Effects of deafness on acoustic characteristics of American English tense/lax vowels in maternal speech to infants
,” J. Acoust. Soc. Am.
132
(2
), 1039
–1049
.60.
Kondaurova
, M. V.
, Bergeson
, T. R.
, and Xu
, H.
(2013
). “Age-related changes in prosodic features of maternal speech to prelingually deaf infants with cochlear implants
,” Infancy
18
(5
), 825
–848
.61.
Kuhl
, P. K.
, Andruski
, J. E.
, Chistovich
, I. A.
, Chistovich
, L. A.
, Kozhevnikova
, E. V.
, Ryskina
, V. L.
, and Lacerda
, F.
(1997
). “Cross-language analysis of phonetic units in language addressed to infants
,” Science
277
(5326
), 684
–686
.62.
Kuznetsova
, A.
, Brockhoff
, P. B.
, and Christensen
, R. H. B.
(2017
). “lmerTest package: Tests in linear mixed effects models
,” J. Stat. Softw.
82
, 1
–26
.63.
Lam
, C.
, and Kitamura
, C.
(2010
). “Maternal interactions with a hearing and hearing-impaired twin: Similarities and differences in speech input, interaction quality, and word production
,” J. Speech Lang. Hear. Res.
53
(3
), 543
–555
.64.
Lam
, C.
, and Kitamura
, C.
(2012
). “Mommy, speak clearly: Induced hearing loss shapes vowel hyperarticulation
,” Dev. Sci.
15
(2
), 212
–221
.65.
Lenth
, R.
, Singmann
, H.
, Love
, J.
, Buerkner
, P.
, and Herve
, M.
(2019
). “Package ‘emmeans’: Estimated marginal means, aka least-squares means
,” The Comprehensive R Archive Network
, pp. 1
–67
.66.
Leong
, V.
, Kalashnikova
, M.
, Burnham
, D.
, and Goswami
, U.
(2014
). “Infant-directed speech enhances temporal rhythmic structure in the envelope
,” in Fifteenth Annual Conference on the International Speech Communication Association
, September 14–18, Singapore.67.
Liu
, H. M.
, Kuhl
, P. K.
, and Tsao
, F. M.
(2003
). “An association between mothers' speech clarity and infants' speech discrimination skills
,” Dev. Sci.
6
(3
), F1
–F10
.68.
Ma
, W.
, Golinkoff
, R. M.
, Houston
, D. M.
, and Hirsh-Pasek
, K.
(2011
). “Word learning in infant-and adult-directed speech
,” Lang. Learn. Dev.
7
(3
), 185
–201
.69.
Macherey
, O.
, and Carlyon
, R. P.
(2014
). “Cochlear implants
,” Curr. Biol.
24
(18
), R878
–R884
.70.
Makowski
, D.
, Lüdecke
, D.
, Ben-Shachar
, M. S.
, Wilson
, M. D.
, Bürkner
, P. C.
, and Mahr
, T.
(2020
). “Package ‘bayestestR’
,” last viewed August 20, 2020; available at https://easystats.github.io/bayestestR/.71.
Mather
, E.
, and Plunkett
, K.
(2011
). “Same items, different order: Effects of temporal variability on infant categorization
,” Cognition
119
(3
), 438
–447
.72.
Martin
, A.
, Schatz
, T.
, Versteegh
, M.
, Miyazawa
, K.
, Mazuka
, R.
, Dupoux
, E.
, and Cristia
, A.
(2015
). “Mothers speak less clearly to infants than to adults: A comprehensive test of the hyperarticulation hypothesis
,” Psychol. Sci.
26
(3
), 341
–347
.73.
Martinez
, A.
, Eisenberg
, L.
, Boothroyd
, A.
, and Visser-Dumont
, L.
(2008
). “Assessing speech pattern contrast perception in infants: Early results on VRASPAC
,” Otol. Neurotol.
29
(2
), 183
–188
.74.
McMurray
, B.
, Kovack-Lesh
, K. A.
, Goodwin
, D.
, and McEchron
, W.
(2013
). “Infant directed speech and the development of speech perception: Enhancing development or an unintended consequence?
,” Cognition
129
(2
), 362
–378
.75.
Miyamoto
, R. T.
, Houston
, D. M.
, and Bergeson
, T.
(2005
). “Cochlear implantation in deaf infants
,” Laryngoscope
115
(8
), 1376
–1380
.76.
Miyazawa
, K.
, Shinya
, T.
, Martin
, A.
, Kikuchi
, H.
, and Mazuka
, R.
(2017
). “Vowels in infant-directed speech: More breathy and more variable, but not clearer
,” Cognition
166
, 84
–93
.77.
Moeller
, M. P.
, and Tomblin
, J. B.
(2015
). “An introduction to the outcomes of children with hearing loss study
,” Ear Hear.
36
, 4s
–13s
.78.
Molfese
, D. L.
(2000
). “Predicting dyslexia at 8 years of age using neonatal brain responses
,” Brain Lang.
72
(3
), 238
–245
.79.
Molfese
, D. L.
, and Molfese
, V. J.
(1985
). “Electrophysiological indices of auditory discrimination in newborn infants: The bases for predicting later language development?
,” Infant Behav. Dev.
8
(2
), 197
–211
.80.
Munhall
, K. G.
, MacDonald
, E. N.
, Byrne
, S. K.
, and Johnsrude
, I.
(2009
). “Talkers alter vowel production in response to real-time formant perturbation even when instructed not to compensate
,” J. Acoust. Soc. Am.
125
(1
), 384
–390
.81.
Narayan
, C. R.
, and McDermott
, L. C.
(2016
). “Speech rate and pitch characteristics of infant-directed speech: Longitudinal and cross-linguistic observations
,” J. Acoust. Soc. Am.
139
(3
), 1272
–1281
.82.
Nicholas
, J. G.
, and Geers
, A. E.
(2007
). “Will they catch up? The role of age at cochlear implantation in the spoken language development of children with severe to profound hearing loss
,” J. Speech Lang. Hear. Res.
50
(4
), 1048
–1062
.83.
Pardo
, J. S.
(2006
). “On phonetic convergence during conversational interaction
,” J. Acoust. Soc. Am.
119
(4
), 2382
–2393
.84.
Peter
, V.
, Kalashnikova
, M.
, Santos
, A.
, and Burnham
, D.
(2016
). “Mature neural responses to infant-directed speech but not adult-directed speech in pre-verbal infants
,” Sci. Rep.
6
, 34273
.85.
R Core Team (2017). “
R: A language and environment for statistical computing
,” R Foundation for Statistical Computing, Vienna, Austria, https://www.r-project.org/ (last viewed August, 20, 2020).86.
Rattanasone
, N. X.
, Burnham
, D.
, and Reilly
, R. G.
(2013
). “Tone and vowel enhancement in Cantonese infant-directed speech at 3, 6, 9, and 12 months of age
,” J. Phon.
41
(5
), 332
–343
.87.
Sarant
, J.
, Harris
, D.
, Bennet
, L.
, and Bant
, S.
(2014
). “Bilateral versus unilateral cochlear implants in children: A study of spoken language outcomes
,” Ear Hear.
35
(4
), 396
–409
.88.
Smiljanić
, R.
, and Bradlow
, A. R.
(2005
). “Production and perception of clear speech in Croatian and English
,” J. Acoust. Soc. Am.
118
(3
), 1677
–1688
.89.
Smiljanić
, R.
, and Bradlow
, A. R.
(2009
). “Speaking and hearing clearly: Talker and listener factors in speaking style changes
,” Lang. Ling. Compass
3
(1
), 236
–264
.90.
Song
, J. Y.
, Demuth
, K.
, and Morgan
, J.
(2010
). “Effects of the acoustic properties of infant-directed speech on infant word recognition
,” J. Acoust. Soc. Am.
128
(1
), 389
–400
.91.
Stern
, D. N.
, Spieker
, S.
, Barnett
, R. K.
, and MacKain
, K.
(1983
). “The prosody of maternal speech: Infant age and context related changes
,” J. Child Lang.
10
(1
), 1
–15
.92.
Szagun
, G.
(2001
). “Language acquisition in young German-speaking children with cochlear implants: Individual differences and implications for conceptions of a ‘sensitive phase
,’” Audiol. Neurotol.
6
(5
), 288
–297
.93.
Szagun
, G.
(2004
). “Individual differences in language acquisition by young children with cochlear implants and implications for a concept of ‘sensitive phase
,’” in International Congress Series
, Vol. 1273
(Elsevier
, Amsterdam, the Netherlands
), pp. 308
–311
.94.
Tang
, P.
, Xu Rattanasone
, N.
, Yuen
, I.
, and Demuth
, K.
(2017
). “Phonetic enhancement of Mandarin vowels and tones: Infant-directed speech and Lombard speech
,” J. Acoust. Soc. Am.
142
(2
), 493
–503
.95.
Thiessen
, E. D.
, Hill
, E. A.
, and Saffran
, J. R.
(2005
). “Infant-directed speech facilitates word segmentation
,” Infancy
7
(1
), 53
–71
.96.
Trainor
, L. J.
, Austin
, C. M.
, and Desjardins
, R. N.
(2000
). “Is infant-directed speech prosody a result of the vocal expression of emotion?
,” Psychol. Sci.
11
(3
), 188
–195
.97.
Tsao
, F. M.
, Liu
, H. M.
, and Kuhl
, P. K.
(2004
). “Speech perception in infancy predicts language development in the second year of life: A longitudinal study
,” Child Dev.
75
(4
), 1067
–1084
.98.
Uther
, M.
, Knoll
, M. A.
, and Burnham
, D.
(2007
). “Do you speak E-NG-LI-SH? A comparison of foreigner-and infant-directed speech
,” Speech Commun.
49
(1
), 2
–7
.99.
Välimaa
, T.
, Kunnari
, S.
, Laukkanen-Nevala
, P.
, Lonka
, E.
, and National Clinical Research Team
. (2018
). “Early vocabulary development in children with bilateral cochlear implants
,” Int. J. Lang. Commun. Disord.
53
(1
), 3
–15
.100.
Vanormelingen
, L.
, De Maeyer
, S.
, and Gillis
, S.
(2016
). “A comparison of maternal and child language in normally-hearing and hearing-impaired children with cochlear implants
,” Lang. Interact. Acq.
7
(2
), 145
–179
.101.
van Wieringen
, A.
, Boudewyns
, A.
, Sangen
, A.
, Wouters
, J.
, and Desloovere
, C.
Unilateral congenital hearing loss in children: Challenges and potentials
. Hearing research
372
, 29
–41
(2019
).102.
Wieland
, E. A.
, Burnham
, E. B.
, Kondaurova
, M.
, Bergeson
, T. R.
, and Dilley
, L. C.
(2015
). “Vowel space characteristics of speech directed to children with and without hearing loss
,” J. Speech Lang. Hear. Res.
58
(2
), 254
–267
.103.
Wong
, P.
, and Ng
, K. W. S.
(2018
). “Testing the hyperarticulation and prosodic hypotheses of child-directed speech: Insights from the perceptual and acoustic characteristics of child-directed Cantonese tones
,” J. Speech Lang. Hear. Res.
61
(8
), 1907
–1925
.104.
Xu
, N.
, Burnham
, D.
, Kitamura
, C.
, and Vollmer-Conna
, U.
(2013
). “Vowel hyperarticulation in parrot-, dog- and infant-directed speech
,” Anthrozoös
26
(3
), 373
–380
.105.
Zeng
, F. G.
(2004
). “Trends in cochlear implants
,” Trends Amplif.
8
(1
), 1
–34
.106.
Zeng
, F. G.
, Tang
, Q.
, and Lu
, T.
(2014
). “Abnormal pitch perception produced by cochlear implant stimulation
,” PloS One
9
(2
), e88662
.107.
Zhang
, Y.
, Koerner
, T.
, Miller
, S.
, Grice-Patil
, Z.
, Svec
, A.
, Akbari
, D.
, and Carney
, E.
(2011
). “Neural coding of formant-exaggerated speech in the infant brain
,” Dev. Sci.
14
(3
), 566
–581
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2020
Acoustical Society of America
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