Although electrophysiological methods of measuring the hearing sensitivity of pinnipeds are not yet as refined as those for dolphins and porpoises, they appear to be a promising supplement to traditional psychophysical procedures. In order to further standardize electrophysiological methods with pinnipeds, a within-subject comparison of psychophysical and auditory steady-state response (ASSR) measures of aerial hearing sensitivity was conducted with a 1.5-yr-old California sea lion. The psychophysical audiogram was similar to those previously reported for otariids, with a U-shape, and thresholds near 10 dB re 20 μPa at 8 and 16 kHz. ASSR thresholds measured using both single and multiple simultaneous amplitude-modulated tones closely reproduced the psychophysical audiogram, although the mean ASSR thresholds were elevated relative to psychophysical thresholds. Differences between psychophysical and ASSR thresholds were greatest at the low- and high-frequency ends of the audiogram. Thresholds measured using the multiple ASSR method were not different from those measured using the single ASSR method. The multiple ASSR method was more rapid than the single ASSR method, and allowed for threshold measurements at seven frequencies in less than 20 min. The multiple ASSR method may be especially advantageous for hearing sensitivity measurements with otariid subjects that are untrained for psychophysical procedures.

1.
Amos
,
D. E.
, and
Koopmans
,
L. H.
(
1963
).
Tables of the Distribution of the Coefficient of Coherence for Stationary Bivariate Gaussian Processes
(
Sandia Corporation
,
Livermore, CA
),
328
p.
2.
Babushina
,
E. S.
,
Zaslavsky
,
G. L.
, and
Yurkevich
,
L. I.
(
1991
). “
Air and underwater hearing of the northern fur seal—Audiograms and auditory frequency discrimination
,”
Biofizika
36
,
904
907
.
3.
Brillinger
,
D. R.
(
1978
). “
A note on the estimation of evoked response
,”
Biol. Cybern.
31
,
141
144
.
4.
Bullock
,
T. H.
,
Ridgway
,
S. H.
, and
Nobuo
,
S.
(
1971
). “
Acoustically evoked potentials in midbrain auditory structures in sea lions (pinnipedia)
,”
Z. Vergl. Physiol.
74
,
372
387
.
5.
Cohen
,
L. T.
,
Rickards
,
F. W.
, and
Clark
,
G. M.
(
1991
). “
A comparison of steady-state evoked potentials to modulated tones in awake and sleeping humans
,”
J. Acoust. Soc. Am.
90
,
2467
2479
.
6.
Cook
,
M. L. H.
,
Varela
,
R. A.
,
Goldstein
,
J. D.
,
McCulloch
,
S. D.
,
Bossart
,
G. D.
,
Finneran
,
J. J.
,
Houser
,
D.
, and
Mann
,
D. A.
(
2006
). “
Beaked whale auditory evoked potential hearing measurements
,”
J. Comp. Physiol. A
192
,
489
495
.
7.
Cook
,
M. L. H.
,
Wells
,
R. S.
, and
Mann
,
D. A.
(
2006
). “
Auditory brainstem response hearing measurements in free-ranging bottlenose dolphins (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
116
,
2504
.
8.
Cornsweet
,
T. N.
(
1962
). “
The staircase method in psychophysics
,”
Am. J. Psychol.
75
,
485
491
.
9.
Dobie
,
R. A.
, and
Wilson
,
M. J.
(
1989
). “
Analysis of auditory evoked potentials by magnitude-squared coherence
,”
Ear Hear.
10
,
2
13
.
10.
Dobie
,
R. A.
, and
Wilson
,
M. J.
(
1996
). “
A comparison of t test, F test, and coherence methods of detecting steady-state auditory-evoked potentials, distortion-product otoacoustic emissions, or other sinusoids
,”
J. Acoust. Soc. Am.
100
,
2236
2246
.
11.
Elberling
,
C.
, and
Wahlgreen
,
O.
(
1985
). “
Estimation of auditory brainstem response, ABR, by means of Bayesian inference
,”
Scand. Audiol.
14
,
89
96
.
12.
Finneran
,
J. J.
(
2003
).
An Integrated Computer-controlled System for Marine Mammal Auditory Testing
(
SSC San Diego
,
San Diego, CA
),
102
p.
13.
Finneran
,
J. J.
(
2008
).
Evoked Response Study Tool (EVREST) User’s Guide
(
SSC San Diego
,
San Diego
),
103
p.
14.
Finneran
,
J. J.
(
2009
). “
Evoked Response Study Tool (EVREST): A portable, rugged system for single and multiple auditory evoked potential measurements
,”
J. Acoust. Soc. Am.
126
,
491
500
.
15.
Finneran
,
J. J.
, and
Houser
,
D. S.
(
2007
). “
Bottlenose dolphin (Tursiops truncatus) steady-state evoked responses to multiple simultaneous sinusoidal amplitude modulated tones
,”
J. Acoust. Soc. Am.
121
,
1775
1782
.
16.
Finneran
,
J. J.
,
Houser
,
D. S.
,
Blasko
,
D.
,
Hicks
,
C.
,
Hudson
,
J.
, and
Osborn
,
M.
(
2008
). “
Estimating bottlenose dolphin (Tursiops truncatus) hearing thresholds from single and multiple simultaneous auditory evoked potentials
,”
J. Acoust. Soc. Am.
123
,
542
551
.
17.
Finneran
,
J. J.
,
Houser
,
D. S.
, and
Schlundt
,
C. E.
(
2007
). “
Objective detection of bottlenose dolphin (Tursiops truncatus) steady-state auditory evoked potentials in response to AM/FM tones
,”
Aquat. Mamm.
33
,
43
54
.
18.
Finneran
,
J. J.
,
Houser
,
D. S.
,
Mase-Guthrie
,
B.
,
Ewing
,
R.Y.
, and
Lingenfelser
,
R.G.
(
2009
). “
Auditory evoked potentials in a stranded Gervais’ beaked whale (Mesoplodon europaeus)
,”
J. Acoust. Soc. Am.
126
,
484
490
.
19.
Haulena
,
M.
, and
Heath
,
R. B.
(
2001
). “
Marine mammal anesthesia
,” in
Marine Mammal Medicine
, edited by
L. A.
Dierauf
and
F. M. D.
Gulland
(
CRC Press
,
Boca Raton
), pp.
655
688
.
20.
Hemilä
,
S.
,
Nummela
,
S.
,
Berta
,
A.
, and
Reuter
,
T.
(
2006
). “
High-frequency hearing in phocid and otariid pinnipeds: An interpretation based on inertial and cochlear constraints (L)
,”
J. Acoust. Soc. Am.
120
,
3463
3466
.
21.
Houser
,
D. S.
, and
Finneran
,
J. J.
(
2006
). “
Variation in the hearing sensitivity of a dolphin population obtained through the use of evoked potential audiometry
,”
J. Acoust. Soc. Am.
120
,
4090
4099
.
22.
Houser
,
D. S.
,
Gomez-Rubio
,
A.
, and
Finneran
,
J. J.
(
2008
). “
Evoked potential audiometry of 13 Pacific bottlenose dolphins (Tursiops truncatus gilli)
,”
Marine Mammal Sci.
24
,
28
41
.
23.
John
,
M. S.
,
Dimitrijevic
,
A.
, and
Picton
,
T. W.
(
2002a
). “
Auditory steady-state responses to exponential modulation envelopes
,”
Ear Hear.
23
,
106
117
.
24.
John
,
M. S.
,
Dimitrijevic
,
A.
, van
Roon
,
P.
, and
Picton
,
T. W.
(
2001
). “
Multiple auditory steady-state responses to AM and FM stimuli
,”
Audiol. Neuro-Otol.
6
,
12
27
.
25.
John
,
M. S.
,
Lins
,
O. G.
,
Boucher
,
B. L.
, and
Picton
,
T. W.
(
1998
). “
Multiple auditory steady-state responses (MASTER): Stimulus and recording parameters
,”
Audiology
37
,
59
82
.
26.
John
,
M. S.
,
Purcell
,
D. W.
,
Dimitrijevic
,
A.
, and
Picton
,
T. W.
(
2002b
). “
Advantages and caveats when recording steady-state responses to multiple simultaneous stimuli
,”
J. Am. Acad. Audiol.
13
,
246
259
.
27.
Johnson
,
C. S.
(
1966
).
Auditory Thresholds of the Bottlenosed Porpoise (Tursiops truncatus, Montagu)
(
U.S. Naval Ordnance Test Station
, NOTS TP 4178,
China Lake
), p.
28
.
28.
Kastak
,
D.
, and
Schusterman
,
R.
(
1998
). “
Low-frequency amphibious hearing in pinnipeds: Methods, measurements, noise, and ecology
,”
J. Acoust. Soc. Am.
103
,
2216
2228
.
29.
Kastak
,
D.
, and
Schusterman
,
R. J.
(
2002
). “
Changes in auditory sensitivity with depth in a free-diving California sea lion (Zalophus californianus)
,”
J. Acoust. Soc. Am.
112
,
329
333
.
30.
Kuwada
,
S.
,
Batra
,
R.
, and
Maher
,
V. L.
(
1986
). “
Scalp potentials of normal and hearing-impaired subjects in response to sinusoidally amplitude-modulated tones
,”
Hearing Res.
21
,
179
192
.
31.
Levitt
,
H.
(
1971
). “
Transformed up-down methods in psyhcoacoustics
,”
J. Acoust. Soc. Am.
49
,
467
477
.
32.
Lins
,
O. G.
, and
Picton
,
T. W.
(
1995
). “
Auditory steady-state responses to multiple simultaneous stimuli
,”
Electroencephalogr. Clin. Neurophysiol.
96
,
420
432
.
33.
Lins
,
O. G.
,
Picton
,
P. E.
,
Picton
,
T. W.
,
Champagne
,
S. C.
, and
Durieux-Smith
,
A.
(
1995
). “
Auditory steady-state responses to tones amplitude-modulated at 80–110 Hz
,”
J. Acoust. Soc. Am.
97
,
3051
3063
.
34.
Moore
,
P. W. B.
, and
Schusterman
,
R. J.
(
1987
). “
Audiometric assessment of northern fur seals, Callorhinus ursinus
,”
Marine Mammal Sci.
3
,
31
53
.
35.
Mulsow
,
J.
, and
Reichmuth
,
C.
(
2007a
). “
Amplitude-versus-rate transfer functions to tone burst stimuli in the California sea lion Zalophus californianus
,”
Bioacoustics
17
,
80
82
.
36.
Mulsow
,
J.
, and
Reichmuth
,
C.
(
2007b
). “
Electrophysiological assessment of temporal resolution in pinnipeds
,”
Aquat. Mamm.
33
,
122
131
.
37.
Mulsow
,
J. L.
, and
Reichmuth
,
C.
(
2010
). “
Psychophysical and electrophysiological aerial audiograms of a Steller sea lion (Eumetopias jubatus)
,”
J. Acoust. Soc. Am.
127
,
2692
2701
.
38.
Mulsow
,
J.
,
Reichmuth
,
C.
,
Gulland
,
F.
,
Rosen
,
D. A. S.
, and
Finneran
,
J. J.
(
2011
). “
Aerial audiograms of several California sea lions (Zalophus californianus) and Steller sea lions (Eumetopias jubatus) measured using single and multiple simultaneous auditory steady-state response methods
,”
J. Exp. Biol
.
214
,
1138
1147
.
39.
Nachtigall
,
P. E.
,
Mooney
,
T. A.
,
Taylor
,
K. A.
,
Miller
,
L. A.
,
Rasmussen
,
M. H.
,
Akamatsu
,
T.
,
Teilmann
,
J.
,
Linnenschmidt
,
M.
, and
Vikingsson
,
G. A.
(
2008
). “
Shipboard measurements of the hearing of the white-beaked dolphin Lagenorhynchus albirostris
,”
J. Exp. Biol.
211
,
642
647
.
40.
Nachtigall
,
P. E.
,
Yuen
,
M. M. L.
,
Mooney
,
T. A.
, and
Taylor
,
K. A.
(
2005
). “
Hearing measurements from a stranded infant Risso’s dolphin, Grampus griseus
,”
J. Exp. Biol.
208
,
4181
4188
.
41.
National Research Council (NRC)
. (
2000
).
Marine Mammals and Low-Frequency Sound: Progress Since 1994
(
National Academy Press
,
Washington, DC
),
146
p.
42.
NRC.
(
2003
).
Ocean Noise and Marine Mammals
(
National Academies Press
,
Washington, DC
),
192
p.
43.
NRC.
(
2005
).
Marine Mammal Populations and Ocean Noise: Determining When Noise Causes Biologically Significant Effects
(
National Academies Press
,
Washington, DC
),
126
p.
44.
Picton
,
T. W.
,
John
,
M. S.
,
Dimitrijevic
,
A.
, and
Purcell
,
D.
(
2003
). “
Human auditory steady-state responses
,”
Int. J. Audiol.
42
,
177
219
.
45.
Ridgway
,
S. H.
, and
Joyce
,
P. L.
(
1975
). “
Studies on seal brain by radiotelemetry
,”
Rapp. P.-V. Reun. Cons. Int. Explor. Mer.
169
,
81
91
.
46.
Schlundt
,
C. E.
,
Dear
,
R. L.
,
Green
,
L.
,
Houser
,
D. S.
,
Finneran
,
J. J.
(
2007
). “
Simultaneously measured behavioral and electrophysiological hearing thresholds in a bottlenose dolphin (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
122
,
615
622
.
47.
Schusterman
,
R. J.
,
Balliet
,
R. F.
, and
Nixon
,
J.
(
1972
). “
Underwater audiogram of the California sea lion by the conditioned vocalization technique
,”
J. Exp. Anal. Behav.
17
,
339
350
.
48.
Schusterman
,
R. J.
,
Southall
,
B.
,
Kastak
,
D.
, and
Kastak
,
C. R.
(
2002
). “
Age-related hearing loss in sea lions and their scientists
,”
J. Acoust. Soc. Am.
111
,
2342
2343
.
49.
Southall
,
B. L.
,
Bowles
,
A. E.
,
Ellison
,
W. T.
,
Finneran
,
J. J.
,
Gentry
,
R. L.
,
Greene
,
C. R.
, Jr.
,
Kastak
,
D.
,
Ketten
,
D. R.
,
Miller
,
J. H.
,
Nachtigall
,
P. E.
,
Richardson
,
W. J.
,
Thomas
,
J. A.
, and
Tyack
,
P. L.
(
2007
). “
Marine mammal noise exposure criteria: Initial scientific recommendations
,”
Aquat. Mamm.
33
,
411
521
.
50.
Southall
,
B. L.
,
Schusterman
,
R. J.
, and
Kastak
,
D.
(
2003
). “
Auditory masking in three pinnipeds: Aerial critical ratios and direct critical bandwidth measurements
,”
J. Acoust. Soc. Am.
114
,
1660
1666
.
51.
Supin
,
A. Y.
,
Popov
,
V. V.
, and
Mass
,
A. M.
(
2001
).
The Sensory Physiology of Aquatic Mammals
(
Kluwer Academic Publishers
,
Boston
),
332
p.
52.
Szymanski
,
M. D.
,
Bain
,
D. E.
,
Kiehl
,
K.
,
Pennington
,
S.
,
Wong
,
S.
, and
Henry
,
K. R.
(
1999
). “
Killer whale (Orcinus orca) hearing: Auditory brainstem response and behavioral audiograms
,”
J. Acoust. Soc. Am.
106
,
1134
1141
.
53.
Wolski
,
L. F.
,
Anderson
,
R. C.
,
Bowles
,
A. E.
, and
Yochem
,
P. K.
(
2003
). “
Measuring hearing in the harbor seal (Phoca vitulina): Comparison of behavioral and auditory brainstem response techniques
,”
J. Acoust. Soc. Am.
113
,
629
637
.
54.
Yuen
,
M. M. L.
,
Nachtigall
,
P. E.
,
Breese
,
M.
, and
Supin
,
A. Y.
(
2005
). “
Behavioral and auditory evoked potential audiograms of a false killer whale (Pseudorca crassidens)
,”
J. Acoust. Soc. Am.
118
,
2688
2695
.
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