To improve speech perception for cochlear implant (CI) users, it is essential to improve the transmission of temporal envelopes. The most common speech processors deliver temporal envelopes via the CI using fixed-rate amplitude modulated (AM) pulse trains. Psychophysical studies suggest that rate modulation (RM) and AM are perceived by a shared temporal integration mechanism, but the potential for them to constructively combine to encode temporal envelopes has yet to be explored. In this experiment, a speech processing strategy called amplitude and rate temporal modulation was developed to encode speech temporal envelopes with simultaneous AM and RM. The strategy was tested for perception of clean speech at 60 and 40 dBA, and 60 dBA speech in noise (+10 dB SNR). The amount of RM was varied and the amount of AM was held constant to determine whether the addition of RM could enhance the perception of temporal envelopes and improve speech understanding. At the lowest RM amount, speech scores were poorest for all speech conditions. For 60 dBA clean speech and speech in noise, speech scores were significantly better at the highest RM amounts, suggesting that RM combined with AM can be used to enhance perception of temporal envelopes.
References
1.
Arai
, T.
, and Greenberg
, S.
(1998
). “Speech intelligibility in the presence of cross-channel spectral asynchrony
,” in Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing
, pp. 933
–936
.2.
Arnoldner
, C.
, Riss
, D.
, Brunner
, M.
, Durisin
, M.
, Baumgartner
, W.-D.
, and Hamzavi
, J.-S.
(2007
). “Speech and music perception with the new fine structure speech coding strategy: Preliminary results
,” Acta Oto-laryngol.
127
, 1298
–1303
.3.
Azadpour
, M.
, and McKay
, C. M.
(2014
). “Processing of speech temporal and spectral information by users of auditory brainstem implants and cochlear implants
,” Ear Hear.
35
, e192
–e203
.4.
Azadpour
, M.
, and Smith
, R. L.
(2016
). “Enhancing speech envelope by integrating hair-cell adaptation into cochlear implant processing
,” Hear. Res.
342
, 48
–57
.5.
Brochier
, T.
, McDermott
, H. J.
, and McKay
, C. M.
(2017
). “The effect of presentation level and stimulation rate on speech perception and modulation detection for cochlear implant users
,” The J. Acoust. Soc. Am.
141
, 4097
–4105
.6.
Brochier
, T.
, McKay
, C.
, and McDermott
, H.
(2018
). “Rate modulation detection thresholds for cochlear implant users
,” J. Acoust. Soc. Am.
143
, 1214
–1222
.7.
De Ruiter
, A. M.
, Debruyne
, J. A.
, Chenault
, M. N.
, Francart
, T.
, and Brokx
, J. P.
(2015
). “Amplitude modulation detection and speech recognition in late-implanted prelingually and postlingually deafened cochlear implant users
,” Ear Hear.
36
, 557
–566
.8.
Fishman
, K. E.
, Shannon
, R. V.
, and Slattery
, W. H.
(1997
). “Speech recognition as a function of the number of electrodes used in the SPEAK cochlear implant speech processor
,” J. Speech, Lang., Hear. Res.
40
, 1201
–1215
.9.
Friesen
, L. M.
, Shannon
, R. V.
, Baskent
, D.
, and Wang
, X.
(2001
). “Speech recognition in noise as a function of the number of spectral channels: Comparison of acoustic hearing and cochlear implants
,” J. Acoust. Soc. Am.
110
, 1150
–1163
.10.
Fu
, Q.-J.
(2002
). “Temporal processing and speech recognition in cochlear implant users
,” Neuroreport
13
, 1635
–1639
.11.
Fu
, Q.-J.
, and Galvin
, J. J.
III (2001
). “Recognition of spectrally asynchronous speech by normal-hearing listeners and Nucleus-22 cochlear implant users
,” J. Acoust. Soc. Am.
109
, 1166
–1172
.12.
Fu
, Q.-J.
, and Shannon
, R. V.
(2000
). “Effect of stimulation rate on phoneme recognition by Nucleus-22 cochlear implant listeners
,” J. Acoust. Soc. Am.
107
, 589
–597
.13.
Garadat
, S. N.
, Zwolan
, T. A.
, and Pfingst
, B. E.
(2012
). “Across-site patterns of modulation detection: Relation to speech recognition
,” J. Acoust. Soc. Am.
131
, 4030
–4041
.14.
Garadat
, S. N.
, Zwolan
, T. A.
, and Pfingst
, B. E.
(2013
). “Using temporal modulation sensitivity to select stimulation sites for processor MAPs in cochlear implant listeners
,” Audiol. Neurotol.
18
, 247
–260
.15.
Geurts
, L.
, and Wouters
, J.
(1999
). “Enhancing the speech envelope of continuous interleaved sampling processors for cochlear implants
,” J. Acoust. Soc. Am.
105
, 2476
–2484
.16.
Gnansia
, D.
, Lazard
, D. S.
, Léger
, A. C.
, Fugain
, C.
, Lancelin
, D.
, Meyer
, B.
, and Lorenzi
, C.
(2014
). “Role of slow temporal modulations in speech identification for cochlear implant users
,” Int. J. Audiol.
53
, 48
–54
.17.
Holden
, L. K.
, Vandali
, A. E.
, Skinner
, M. W.
, Fourakis
, M. S.
, and Holden
, T. A.
(2005
). “Speech recognition with the advanced combination encoder and transient emphasis spectral maxima strategies in nucleus 24 recipients
,” J. Speech, Lang., Hear. Res.
48
, 681
–701
.18.
Koning
, R.
, and Wouters
, J.
(2016
). “Speech onset enhancement improves intelligibility in adverse listening conditions for cochlear implant users
,” Hear. Res.
342
, 13
–22
.19.
Luo
, X.
, and Fu
, Q.-J.
(2007
). “Frequency modulation detection with simultaneous amplitude modulation by cochlear implant users
,” J. Acoust. Soc. Am.
122
, 1046
–1054
.20.
Magnusson
, L.
(2011
). “Comparison of the fine structure processing (FSP) strategy and the CIS strategy used in the MED-EL cochlear implant system: Speech intelligibility and music sound quality
,” Int. J. Audiol.
50
, 279
–287
.21.
McKay
, C. M.
, Henshall
, K. R.
, Farrell
, R. J.
, and McDermott
, H. J.
(2003
). “A practical method of predicting the loudness of complex electrical stimuli
,” J. Acoust. Soc. Am.
113
, 2054
–2063
.22.
McKay
, C. M.
, Lim
, H. H.
, and Lenarz
, T.
(2013
). “Temporal processing in the auditory system
,” J. Assoc. Res. Otolaryngol.
14
, 103
–124
.23.
McKay
, C. M.
, and McDermott
, H. J.
(1998
). “Loudness perception with pulsatile electrical stimulation: The effect of interpulse intervals
,” J. Acoust. Soc. Am.
104
, 1061
–1074
.24.
McKay
, C. M.
, Remine
, M. D.
, and McDermott
, H. J.
(2001
). “Loudness summation for pulsatile electrical stimulation of the cochlea: Effects of rate, electrode separation, level, and mode of stimulation
,” J. Acoust. Soc. Am.
110
, 1514
–1524
.25.
Nie
, K.
, Barco
, A.
, and Zeng
, F.-G.
(2006
). “Spectral and temporal cues in cochlear implant speech perception
,” Ear Hear.
27
, 208
–217
.26.
Nie
, K.
, Stickney
, G.
, and Zeng
, F.-G.
(2005
). “Encoding frequency modulation to improve cochlear implant performance in noise
,” IEEE Trans, Biomed. Eng.
52
, 64
–73
.27.
Oxenham
, A. J.
(2001
). “Forward masking: Adaptation or integration?
,” J. Acoust. Soc. Am.
109
, 732
–741
.28.
Oxenham
, A. J.
, and Moore
, B. C.
(1994
). “Modeling the additivity of nonsimultaneous masking
,” Hear. Res.
80
, 105
–118
.29.
Plack
, C. J.
, Oxenham
, A. J.
, and Drga
, V.
(2002
). “Linear and nonlinear processes in temporal masking
,” Acta Acust. Acust.
88
, 348
–358
.30.
Saberi
, K.
, and Perrott
, D. R.
(1999
). “Cognitive restoration of reversed speech
,” Nature
398
, 760
.31.
Shannon
, R. V.
(2002
). “The relative importance of amplitude, temporal, and spectral cues for cochlear implant processor design
,” Am. J. Audiol.
11
, 124
–127
.32.
Shannon
, R. V.
, Zeng
, F.-G.
, Kamath
, V.
, Wygonski
, J.
, and Ekelid
, M.
(1995
). “Speech recognition with primarily temporal cues
,” Science
270
, 303
–304
.33.
Vandali
, A. E.
(2001
). “Emphasis of short-duration acoustic speech cues for cochlear implant users
,” J. Acoust. Soc. Am.
109
, 2049
–2061
.34.
Vandali
, A. E.
, Whitford
, L. A.
, Plant
, K. L.
, and Clark
, G. M.
(2000
). “Speech perception as a function of electrical stimulation rate: Using the Nucleus 24 cochlear implant system
,” Ear Hear.
21
, 608
–624
.35.
Weatherby
, A.
, Henshall
, K. R.
, and McKay
, C. M.
(2003
). “The effects of frequency response on speech perception for cochlear implant users
,” J. Am. Acad. Audiol.
14
, 582
–591
.36.
Won
, J. H.
, Drennan
, W. R.
, Nie
, K.
, Jameyson
, E. M.
, and Rubinstein
, J. T.
(2011
). “Acoustic temporal modulation detection and speech perception in cochlear implant listeners
,” J. Acoust. Soc. Am.
130
, 376
–388
.37.
Wouters
, J.
, McDermott
, H. J.
, and Francart
, T.
(2015
). “Sound coding in cochlear implants: From electric pulses to hearing
,” IEEE Signal Process. Mag.
32
, 67
–80
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2018
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