Simulations of monaural cochlear implants in normal hearing listeners have shown that the deleterious effects of upward spectral shifting on speech perception can be overcome with training. This study simulates bilateral stimulation with a unilateral spectral shift to investigate whether listeners can adapt to upward-shifted speech information presented together with contralateral unshifted information. A six-channel, dichotic, interleaved sine-carrier vocoder simulated a binaurally mismatched frequency-to-place map. Odd channels were presented to one ear with an upward frequency shift equivalent to 6 mm on the basilar membrane, while even channels were presented to the contralateral ear unshifted. In Experiment 1, listeners were trained for 5.3 h with either the binaurally mismatched processor or with just the shifted monaural bands. In Experiment 2, the duration of training was 10 h, and the trained condition alternated between those of Experiment 1. While listeners showed learning in both experiments, intelligibility with the binaurally mismatched processor never exceeded, intelligibility with just the three unshifted bands, suggesting that listeners did not benefit from combining the mismatched maps, even though there was clear scope to do so. Frequency-place map alignment may thus be of importance when optimizing bilateral devices of the type studied here.

1.
Azadpour
,
M.
(
2008
). “
Perceptual learning in speech processing: Comprehending spectrally-rotated speech
,” Ph.D. dissertation,
University of Trieste
, Trieste, Italy.
2.
Bench
,
J.
,
Kowal
,
A.
, and
Bamford
,
J. M.
(
1979
). “
The BKB (Bamford-Kowal-Bench) sentence lists for partially hearing children
,”
Br. J. Audiol.
13
,
108
112
.
3.
Blesser
,
B.
(
1972
). “
Speech perception under conditions of spectral transformation I. Phonetic characteristics
,”
J. Speech Hear. Res.
15
,
5
41
.
4.
Broadbent
,
D. E.
, and
Ladefoged
,
P.
(
1957
). “
On the fusion of sounds reaching different sense organs
,”
J. Acoust. Soc. Am.
29
,
708
710
.
5.
Carrell
,
T.
, and
Opie
,
J. M.
(
1992
). “
The effect of amplitude comodulation on auditory object formation in sentence perception
,”
Percept. Psychophys.
52
,
437
445
.
6.
Ching
,
T. Y. C.
(
2005
). “
The evidence calls for making binaural-bimodal fittings routine
,”
Hear. J.
58
,
32
41
.
7.
Ching
,
T. Y. C.
,
Incerti
,
P.
, and
Hill
,
M.
(
2004
). “
Binaural benefits for adults who use hearing aids and cochlear implants in opposite ears
,”
Ear Hear.
25
,
9
21
.
8.
Ching
,
T. Y. C.
,
Incerti
,
P.
,
Hill
,
M.
, and
van Wanrooy
,
E.
(
2006
). “
An overview of binaural advantages for children and adults who use binaural/bimodal hearing devices
,”
Audiology and Neurotology
11
,
6
11
.
10.
Cutting
,
J. E.
(
1976
). “
Auditory and linguistic processes in speech perception: Inferences from six fusions in dichotic listening
,”
Psychol. Rev.
83
,
114
140
.
11.
Davis
,
M. H.
,
Johnsrude
,
I. S.
, and
Hervais-Adelman
,
A. T. K. M. C.
(
2005
). “
Lexical information drives perceptual learning of distorted speech: Evidence from the comprehension of noise-vocoded sentences
,”
J. Exp. Psychol. Gen.
134
,
222
241
.
12.
De Filippo
,
C. L.
, and
Scott
,
B. L.
(
1978
). “
A method for training and evaluating the reception of ongoing speech
,”
J. Acoust. Soc. Am.
63
,
1186
1192
.
13.
Dorman
,
M. F.
, and
Dahlstrom
,
L.
(
2004
). “
Speech understanding by cochlear-implant patients with different left- and right-ear electrode arrays
,”
Ear Hear.
25
,
191
194
.
14.
Dorman
,
M. F.
,
Loizou
,
P. C.
, and
Rainey
,
D.
(
1997a
). “
Simulating the effect of cochlear-implant electrode insertion depth on speech understanding
,”
J. Acoust. Soc. Am.
102
,
2993
2996
.
15.
Dorman
,
M. F.
,
Loizou
,
P. C.
, and
Rainey
,
D.
(
1997b
). “
Speech intelligibility as a function of the number of channels of stimulation for signal processors using sine-wave and noise-band outputs
,”
J. Acoust. Soc. Am.
102
,
2403
2411
.
17.
Faulkner
,
A.
(
2006
). “
Adaptation to distorted frequency-to-place maps: Implications of simulations in normal listeners for cochlear implants and electroacoustic stimulation
,”
Audiology and Neurotology
11
,
21
26
.
18.
Faulkner
,
A.
,
Rosen
,
S.
, and
Norman
,
C.
(
2006
). “
The right information may matter more than frequency-place alignment: Simulations of frequency-aligned and upward shifting cochlear implant processors for a shallow electrode array insertion
,”
Ear Hear.
27
,
139
152
.
19.
Faulkner
,
A.
,
Rosen
,
S.
, and
Stanton
,
D.
(
2003
). “
Simulations of tonotopically mapped speech processors for cochlear implant electrodes varying in insertion depth
,”
J. Acoust. Soc. Am.
113
,
1073
1080
.
20.
Faulkner
,
A.
,
Rosen
,
S.
, and
Wilkinson
,
L.
(
2001
). “
Effects of the number of channels and speech-to-noise ratio on rate of connected discourse tracking through a simulated cochlear implant processor
,”
Ear Hear.
22
,
431
438
.
21.
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
.
22.
Fitzgerald
,
M. B.
,
Tan
,
C. -T.
, and
Svirsky
,
M. A.
(
2007
). “
Customized selection of frequency maps in an acoustic simulation of a cochlear implant
, in
Conference on Implantable Auditory Prostheses
, Tahoe City, CA.
23.
Francart
,
T.
, and
Wouters
,
J.
(
2007
). “
Perception of across-frequency interaural level differences
,”
J. Acoust. Soc. Am.
122
,
2826
2831
.
24.
Fu
,
Q. -J.
, and
Galvin
,
J. J.
 III
(
2003
). “
The effects of short-term training for spectrally mismatched noise-band speech
,”
J. Acoust. Soc. Am.
113
,
1065
1072
.
25.
Fu
,
Q. -J.
,
Galvin
,
J. J.
 III
,
Wang
,
X.
, and
Nogaki
,
G.
(
2005a
). “
Moderate auditory training can improve speech performance of adult cochlear implant patients
,”
ARLO
6
,
106
111
.
26.
Fu
,
Q. -J.
,
Nogaki
,
G.
, and
Galvin
,
J. J.
 III
(
2005b
). “
Auditory training with spectrally shifted speech: Implications for cochlear implant patient auditory rehabilitation
,”
J. Assoc. Res. Otolaryngol.
6
,
180
189
.
27.
Fu
,
Q. -J.
, and
Shannon
,
R. V.
(
1999
). “
Recognition of spectrally degraded and frequency-shifted vowels in acoustic and electric hearing
,”
J. Acoust. Soc. Am.
105
,
1889
1900
.
28.
Fu
,
Q. -J.
,
Shannon
,
R. V.
, and
Galvin
,
J. J.
 III
(
2002
). “
Perceptual learning following changes in the frequency-to-electrode assignment with the Nucleus-22 cochlear implant
,”
J. Acoust. Soc. Am.
112
,
1664
1674
.
29.
Grant
,
K. W.
,
Braida
,
L. D.
, and
Renn
,
R. J.
(
1994
). “
Auditory supplements to speechreading: Combining amplitude envelope cues from different spectral regions of speech
,”
J. Acoust. Soc. Am.
95
,
1065
1073
.
30.
Greenwood
,
D. D.
(
1990
). “
A cochlear frequency-position function for several species — 29 years later
,”
J. Acoust. Soc. Am.
87
,
2592
2605
.
31.
Hamzavi
,
J.
,
Pok
,
S. M.
,
Gstoettner
,
W.
, and
Baumgartner
,
W. -D.
(
2004
). “
Speech perception with a cochlear implant used in conjunction with a hearing aid in the opposite ear
,”
Int. J. Audiol.
43
,
61
65
.
32.
Iwaki
,
T.
,
Matsushiro
,
N.
,
Mah
,
S. -R.
,
Sato
,
T.
,
Yasuoka
,
E.
,
Yamamoto
,
K. -I.
, and
Kubo
,
T.
(
2004
). “
Comparison of speech perception between monaural and binaural hearing in cochlear implant patients
,”
Acta Oto-Laryngol.
124
,
358
362
.
33.
Ketten
,
D. R.
,
Skinner
,
M. W.
,
Wang
,
G.
,
Vannier
,
M. W.
,
Gates
,
G. A.
, and
Neely
,
J. G.
(
1998
). “
In vivo measures of cochlear length and insertion depth of Nucleus cochlear implant electrode arrays
,”
Ann. Otol. Rhinol. Laryngol.
107
,
1
16
.
34.
Lawson
,
D.
,
Brill
,
S.
,
Wolford
,
R.
,
Wilson
,
B.
, and
Schatzer
,
R.
(
2000
). Speech Processors for Auditory Prostheses: Ninth quarterly progress report.
35.
Li
,
T.
, and
Fu
,
Q. -J.
(
2007
). “
Perceptual adaptation to spectrally shifted vowels: Training with nonlexical labels
,”
J. Assoc. Res. Otolaryngol.
8
,
32
41
.
36.
Li
,
T.
,
Galvin
,
J. J.
 III
, and
Fu
,
Q. -J.
(
2009
). “
Interactions between unsupervised learning and the degree of spectral mismatch on short-term perceptual adaptation to spectrally shifted speech
,”
Ear Hear.
30
,
238
249
.
37.
Litovsky
,
R.
,
Parkinson
,
A.
,
Arcaroli
,
J.
, and
Sammeth
,
C.
(
2006
). “
Simultaneous bilateral cochlear implantation in adults: A multicenter clinical study
,”
Ear Hear.
27
,
714
731
.
38.
Loizou
,
P. C.
,
Mani
,
A.
, and
Tu
,
Z.
(
2003
). “
Dichotic speech recognition in noise using reduced spectral cues
,”
J. Acoust. Soc. Am.
114
,
475
483
.
39.
Loizou
,
P. C.
,
Dorman
,
M. F.
, and
Tu
,
Z.
(
1999
). “
On the number of channels needed to understand speech
,”
J. Acoust. Soc. Am.
106
,
2097
2103
.
40.
Long
,
C. J.
,
Deeks
,
J. M.
,
Leow
,
M. -C.
, and
Carlyon
,
R. P.
(
2004
). “
Simulations of bilateral cochlear implant speech reception in noise
,” in
Association for Research in Otolaryngology Midwinter Meeting
, Daytona Beach, FL.
41.
Long
,
C. J.
,
Eddington
,
D. K.
,
Colburn
,
H. S.
, and
Rabinowitz
,
W. M.
(
2003
). “
Binaural sensitivity as a function of interaural electrode position with a bilateral cochlear implant user
,”
J. Acoust. Soc. Am.
114
,
1565
1574
.
42.
Macleod
,
A.
, and
Summerfield
,
Q.
(
1990
). “
A procedure for measuring auditory and audio-visual speech-reception thresholds for sentences in noise: Rationale, evaluation and recommendations for use
,”
Br. J. Audiol.
24
,
29
43
.
43.
Mani
,
A.
,
Loizou
,
P. C.
,
Shoup
,
A.
,
Roland
,
P.
, and
Kruger
,
P.
(
2004
). “
Dichotic speech recognition by bilateral cochlear implant users
,” International Congress Series,
1273
,
466
469
.
44.
Miller
,
G. A.
, and
Nicely
,
P. E.
(
1955
). “
An analysis of perceptual confusions among some English consonants
,”
J. Acoust. Soc. Am.
27
,
338
352
.
45.
Mills
,
J. H.
,
Dubno
,
J. R.
, and
He
,
N. J.
(
1996
). “
Masking by ipsilateral and contralateral maskers
,”
J. Acoust. Soc. Am.
100
,
3336
3344
.
46.
Mosnier
,
I.
,
Sterkers
,
O.
,
Bebear
,
J. P.
,
Godey
,
B.
,
Robier
,
A.
,
Deguine
,
O.
,
Fraysse
,
B.
,
Bordure
,
P.
,
Mondain
,
M.
,
Bouccara
,
D.
,
Bozorg-Grayeli
,
A.
,
Borel
,
S.
,
Ambert-Dahan
,
E.
, and
Ferrary
,
E.
(
2009
). “
Speech performance and sound localization in a complex noisy environment in bilaterally implanted adult patients
,”
Audiology and Neurotology
14
,
106
114
.
47.
Nuetzel
,
J. M.
, and
Hafter
,
E. R.
(
1981
). “
Discrimination of interaural delays in complex waveforms: Spectral effects
,”
J. Acoust. Soc. Am.
69
,
1112
1118
.
48.
Robinson
,
D.
, and
Dadson
,
R. S.
(
1956
). “
A redetermination of the equal-loudness relations for pure tones
,”
Br. J. Appl. Phys.
7
,
166
181
.
49.
Rosen
,
S.
,
Faulkner
,
A.
, and
Wilkinson
,
L.
(
1999
). “
Adaptation by normal listeners to upward spectral shifts of speech: Implications for cochlear implants
,”
J. Acoust. Soc. Am.
106
,
3629
3636
.
50.
Rothauser
,
E. H.
,
Chapman
,
N. D.
,
Guttman
,
N.
,
Nordby
,
K. S.
,
Silbiger
,
H. R.
,
Urbanek
,
G. E.
, and
Weinstock
,
M.
(
1969
). “
IEEE recommended practice for speech quality measurements
,”
IEEE Trans. Audio Electroacoust.
17
,
227
246
.
51.
Rubin
,
B. A.
,
Uchanski
,
R. M.
, and
Braida
,
L. D.
(
1992
). “
Integration of acoustic cues for consonants across frequency bands (A)
,”
J. Acoust. Soc. Am.
91
,
2473
2474
.
52.
Shannon
,
R. V.
,
Zeng
,
F. -G.
, and
Wygonski
,
J.
(
1998
). “
Speech recognition with altered spectral distribution of envelope cues
,”
J. Acoust. Soc. Am.
104
,
2467
2476
.
53.
Skinner
,
M. W.
,
Ketten
,
D. R.
,
Holden
,
L. K.
,
Harding
,
G. W.
,
Smith
,
P. G.
,
Gates
,
G. A.
,
Neely
,
J. G.
,
Kletzker
,
G. R.
,
Brunsden
,
B.
, and
Blocker
,
B.
(
2002
). “
CT-derived estimation of cochlear morphology and electrode array position in relation to word recognition in Nucleus-22 recipients
,”
J. Assoc. Res. Otolaryngol.
3
,
332
350
.
54.
Smith
,
M. W.
, and
Faulkner
,
A.
(
2006
). “
Perceptual adaptation by normally hearing listeners to a simulated “hole” in hearing
,”
J. Acoust. Soc. Am.
120
,
4019
4030
.
56.
Smith
,
Z. M.
, and
Delgutte
,
B.
(
2007
). “
Using evoked potentials to match interaural electrode pairs with bilateral cochlear implants
,”
J. Assoc. Res. Otolaryngol.
8
,
134
151
.
57.
Souza
,
P.
, and
Rosen
,
S.
(
2009
). “
Effects of envelope bandwidth on the intelligibility of sine- and noise-vocoded speech
,”
J. Acoust. Soc. Am.
126
,
792
805
.
58.
Stacey
,
P.
, and
Summerfield
,
Q.
(
2007
). “
Effectiveness of computer-based auditory training in improving the perception of noise-vocoded speech
,”
J. Acoust. Soc. Am.
121
,
2923
2935
.
59.
Stakhovskaya
,
O.
,
Sridhar
,
D.
,
Bonham
,
B.
, and
Leake
,
P.
(
2007
). “
Frequency map for the human cochlear spiral ganglion: Implications for cochlear implants
,”
J. Assoc. Res. Otolaryngol.
8
,
220
233
.
60.
Svirsky
,
M. A.
,
Silveira
,
A.
,
Neuburger
,
H.
,
Teoh
,
S. -W.
,
Helms
,
J.
, and
Suárez
,
H.
(
2004
). “
Long-term auditory adaptation to a modified peripheral frequency map
,”
Acta Oto-Laryngol.
124
,
381
386
.
61.
Tyler
,
R. S.
, and
Summerfield
,
Q.
(
1996
). “
Cochlear implantation: Relationships with research on auditory deprivation and acclimatization
,”
Ear. Hear.
17
,
38S
50S
.
63.
Tyler
,
R. S.
,
Dunn
,
C. C.
,
Witt
,
S. A.
, and
Noble
,
W. G.
(
2007
). “
Speech perception and localization with adults with bilateral sequential cochlear implants
,”
Ear Hear.
28
,
86S
90S
.
65.
van Hoesel
,
R.
,
Ramsden
,
R.
, and
O’Driscoll
,
M.
(
2002
). “
Sound-direction identification, interaural time delay discrimination, and speech intelligibility advantages in noise for a bilateral cochlear implant user
,”
Ear Hear.
23
,
137
149
.
67.
Wackym
,
P. A.
,
Runge-Samuelson
,
C. L.
,
Firszt
,
J. B.
,
Alkaf
,
F. M.
, and
Burg
,
L. S.
(
2007
). “
More challenging speech-perception tasks demonstrate binaural benefit in bilateral cochlear implant users
,”
Ear Hear.
28
,
80S
85S
.
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