Measurement of the auditory steady-state response (ASSR) is increasingly used to assess marine mammal hearing. These tests normally entail measuring the ASSR to a sequence of sinusoidally amplitude modulated tones, so that the ASSR amplitude function can be defined and the auditory threshold estimated. In this study, an alternative method was employed, where the ASSR was elicited by an amplitude modulated stimulus whose sound pressure level was slowly varied, or “swept,” over a range of levels believed to bracket the threshold. The ASSR amplitude function was obtained by analyzing the resulting grand average evoked potential using a short-time Fourier transform. The suitability of this technique for hearing assessment of bottlenose dolphins and California sea lions was evaluated by comparing ASSR amplitude functions and thresholds obtained with swept amplitude and discrete, constant amplitude stimuli. When factors such as the number of simultaneous tones, the number of averages, and the frequency analysis window length were taken into account, the performance and time required for the swept-amplitude and discrete stimulus techniques were similar. The decision to use one technique over another depends on the relative importance of obtaining suprathreshold information versus the lowest possible thresholds.

1.
Brillinger
,
D. R.
(
1978
). “
A Note On The Estimation Of Evoked Response
,”
Biol. Cybern.
31
,
141
144
.
2.
Campbell
,
F. W.
,
Atkinson
,
J.
,
Francis
,
M. R.
, and
Green
,
D. M.
(
1977
). “
Estimation of auditory thresholds using evoked potentials
,” in
Progress in Clinical Neurophysiology
, edited by
J. E.
Desmedt
(
Karger
,
Basel
), pp.
68
78
.
3.
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
.
4.
Cook
,
M. L. H.
,
Wells
,
R. S.
, and
Mann
,
D. A.
(
2004
). “
Auditory brainstem response hearing measurements in free-ranging bottlenose dolphins (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
116
,
2504
.
5.
Dobie
,
R. A.
, and
Wilson
,
M. J.
(
1989
). “
Analysis of auditory evoked potentials by magnitude-squared coherence
,”
Ear Hear.
10
,
2
13
.
6.
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
.
7.
Dolphin
,
W. F.
(
1995
). “
Steady-state auditory evoked potentials in three cetacean species elicited using amplitude-modulated stimuli
,” in
Sensory Systems of Aquatic Mammals
, edited by
R. A.
Kastelein
,
J. A.
Thomas
, and
P. E.
Nachtigall
(
De Spil Publishers
,
Woerden, The Netherlands
), pp.
25
47
.
8.
Dolphin
,
W. F.
(
1996
). “
Auditory evoked responses to amplitude modulated stimuli consisting of multiple envelope components
,”
J. Comp. Physiol., A
179
,
113
121
.
9.
Dolphin
,
W. F.
,
Au
,
W. W.
,
Nachtigall
,
P. E.
, and
Pawloski
,
J.
(
1995
). “
Modulation rate transfer functions to low-frequency carriers in three species of cetaceans
,”
J. Comp. Physiol., A
177
,
235
245
.
10.
Elberling
,
C.
, and
Wahlgreen
,
O.
(
1985
). “
Estimation of auditory brainstem response, ABR, by means of Bayesian inference
,”
Scand. Audiol.
14
,
89
96
.
11.
Finneran
,
J. J.
(
2008
). “
Evoked Response Study Tool (EVREST) User’s Guide
,”
SSC San Diego Technical Document No. 3226
(
SSC San Diego
,
San Diego
).
12.
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
.
13.
Finneran
,
J. J.
,
Carder
,
D. A.
,
Schlundt
,
C. E.
, and
Dear
,
R. L.
(
2010
). “
Growth and recovery of temporary threshold shift (TTS) at 3 kHz in bottlenose dolphins (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
127
,
3256
3266
.
14.
Finneran
,
J. J.
, and
Houser
,
D. S.
(
2006
). “
Comparison of in-air evoked potential and underwater behavioral hearing thresholds in four bottlenose dolphins (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
119
,
3181
3192
.
15.
Finneran
,
J. J.
, and
Houser
,
D. S.
(
2007
). “
Bottlenose dolphin (Tursiops truncatus) steady-state evoked responses to multiple simultaneous sinusoidal amplitude modulated tones
,”
Journal of the Acoustical Society of America
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.
,
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
.
18.
Finneran
,
J. J.
,
Houser
,
D. S.
, and
Schlundt
,
C. E.
(
2007a
). “
Objective detection of bottlenose dolphin (Tursiops truncatus) steady-state auditory evoked potentials in response to AM/FM tones
,”
Aquat. Mamm.
33
,
43
54
.
19.
Finneran
,
J. J.
,
London
,
H. R.
, and
Houser
,
D. S.
(
2007b
). “
Modulation rate transfer functions in bottlenose dolphins (Tursiops truncatus) with normal hearing and high-frequency hearing loss
,”
J. Comp. Physiol., A
193
,
835
843
.
20.
Finneran
,
J. J.
, and
Schlundt
,
C. E.
(
2007
). “
Underwater sound pressure variation and bottlenose dolphin (Tursiops truncatus) hearing thresholds in a small pool
,”
J. Acoust. Soc. Am.
122
,
606
614
.
21.
Galambos
,
R.
,
Makeig
,
S.
, and
Talmachoff
,
P. J.
(
1981
). “
A 40-Hz auditory potential recorded from the human scalp
,”
Proc. Natl. Acad. Sci. U.S.A.
78
,
2643
2647
.
22.
Hall
,
J. W.
(
1979
). “
Auditory brainstem frequency following responces to waveform envelope periodicity
,”
Science
205
,
1297
1299
.
23.
Hoke
,
M.
,
Ross
,
B.
,
Wickesberg
,
R.
, and
Lutkenhoner
,
B.
(
1984
). “
Weighted averaging—theory and application to electric response audiometry
,”
Electroencephalogr. Clinical Neurophysiol.
57
,
484
489
.
24.
Houser
,
D. S.
,
Crocker
,
D. E.
, and
Finneran
,
J. J.
(
2008a
). “
Click-evoked potentials in a large marine mammal, the adult male northern elephant seal (Mirounga angustirostris)
,”
J. Acoust. Soc. Am.
124
,
44
47
.
25.
Houser
,
D. S.
, and
Finneran
,
J. J.
(
2006a
). “
A comparison of underwater hearing sensitivity in bottlenose dolphins (Tursiops truncatus) determined by electrophysiological and behavioral methods
,”
J. Acoust. Soc. Am.
120
,
1713
1722
.
26.
Houser
,
D. S.
, and
Finneran
,
J. J.
(
2006b
). “
Variation in the hearing sensitivity of a dolphin population obtained through the use of evoked potential audiometry
,”
J. Acoust. Soc. Am.
120
,
4090
4099
.
27.
Houser
,
D. S.
,
Gomez-Rubio
,
A.
, and
Finneran
,
J. J.
(
2008b
). “
Evoked potential audiometry of 13 Pacific bottlenose dolphins (Tursiops truncatus gilli)
,”
Marine Mammal Sci.
24
,
28
41
.
28.
Klishin
,
V. O.
,
Popov
,
V. V.
, and
Supin
,
A. Y.
(
2000
). “
Hearing capabilities of a beluga whale, Delphinapterus leucas
,”
Aquat. Mamm.
26
,
212
228
.
29.
Linden
,
R. D.
,
Campbell
,
K. B.
,
Hamel
,
G.
, and
Picton
,
T. W.
(
1985
). “
Human auditory steady state evoked potentials during sleep
,”
Ear Hear.
6
,
167
174
.
30.
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
.
31.
Lins
,
O. G.
, and
Picton
,
T. W.
(
1995
). “
Auditory steady-state responses to multiple simultaneous stimuli
,”
Electroencephalogr. Clinical Neurophysiol.
96
,
420
432
.
32.
Mooney
,
T. A.
,
Nachtigall
,
P. E.
,
Taylor
,
K. A.
,
Rasmussen
,
M. H.
, and
Miller
,
L. A.
(
2009
). “
Auditory temporal resolution of a wild white-beaked dolphin (Lagenorhynchus albirostris)
,”
J. Comp. Physiol., A
195
,
375
384
.
33.
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
.
34.
Mulsow
,
J.
, and
Reichmuth
,
C.
(
2007b
). “
Electrophysiological assessment of temporal resolution in pinnipeds
,”
Aquat. Mamm.
33
,
122
131
.
35.
Mulsow
,
J. L.
,
Finneran
,
J. J.
, and
Houser
,
D. S.
(
2011
). “
California sea lion (Zalophus californianus) aerial hearing sensitivity measured using auditory steady-state response and psychophysical methods
,”
J. Acoust. Soc. Am.
129
,
2298
2306
.
36.
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
.
37.
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
.
38.
Nachtigall
,
P. E.
,
Supin
,
A. Y.
,
Amundin
,
M.
,
Roken
,
B.
,
Møller
,
T.
,
Mooney
,
T. A.
,
Taylor
,
K. A.
, and
Yuen
,
M.
(
2007
). “
Polar bear Ursus maritimus hearing measured with auditory evoked potentials
,”
J. Exp. Biol.
210
,
1116
1122
.
39.
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
.
40.
Picton
,
T. W.
,
John
,
M. S.
,
Dimitrijevic
,
A.
, and
Purcell
,
D.
(
2003
). “
Human auditory steady-state responses
,”
Int. J. Audiol.
42
,
177
219
.
41.
Picton
,
T. W.
,
Skinner
,
C. R.
,
Champagne
,
S. C.
,
Kellett
,
A. J.
, and
Maiste
,
A. C.
(
1987
). “
Potentials evoked by the sinusoidal modulation of the amplitude or frequency of a tone
,”
J. Acoust. Soc. Am.
82
,
165
178
.
42.
Picton
,
T. W.
,
van Roon
,
P.
, and
John
,
M. S.
(
2007
). “
Human auditory steady-state responses during sweeps of intensity
,”
Ear Hear.
28
,
542
557
.
43.
Popov
,
V. V.
,
Supin
,
A. Y.
, and
Klishin
,
V. O.
(
1997
). “
Paradoxical lateral suppression in the dolphin’s auditory system: weak sounds suppress response to strong sounds
,”
Neurosci. Lett.
234
,
51
54
.
44.
Popov
,
V. V.
,
Supin
,
A. Y.
, and
Klishin
,
V. O.
(
1998
). “
Lateral suppression of rhythmic evoked responses in the dolphin’s auditory system
,”
Hear. Res.
126
,
126
134
.
45.
Popov
,
V. V.
,
Supin
,
A. Y.
,
Pletenko
,
M. G.
,
Tarakanov
,
M. B.
,
Klishin
,
V. O.
,
Bulgakova
,
T. N.
, and
Rosanova
,
E. I.
(
2007
). “
Audiogram variability in normal bottlenose dolphins (Tursiops truncatus)
,”
Aquat. Mamm.
33
,
24
33
.
46.
Regan
,
D.
(
1975
). “
Colour coding of pattern responses in man investigated by evoked potential feedback and direct plot techniques
,”
Vision Res.
15
,
175
183
.
47.
Rodriguez
,
R.
,
Picton
,
T.
,
Linden
,
D.
,
Hamel
,
G.
, and
Laframboise
,
G.
(
1986
). “
Human auditory steady state responses: effects of intensity and frequency
,”
Ear Hear.
7
,
300
313
.
48.
Schlundt
,
C. E.
,
Dear
,
R. L.
,
Green
,
L.
,
Houser
,
D. S.
, and
Finneran
,
J. J.
(
2007
). “
Simultaneously measured behavioral and electrophysiological hearing thresholds in a bottlenose dolphin (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
122
,
615
622
.
49.
Schlundt
,
C. E.
,
Finneran
,
J. J.
,
Branstetter
,
B. K.
,
Dear
,
R. L.
,
Houser
,
D. S.
, and
Hernandez
,
E.
(
2008
). “
Evoked potential and behavioral hearing thresholds in nine bottlenose dolphins (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
123
,
3506
A
.
50.
Stapells
,
D. R.
,
Linden
,
D.
,
Suffield
,
J. B.
,
Hamel
,
G.
, and
Picton
,
T. W.
(
1984
). “
Human auditory steady state potentials
,”
Ear Hear.
5
,
105
113
.
51.
Stapells
,
D. R.
,
Makeig
,
S.
, and
Galambos
,
R.
(
1987
). “
Auditory steady-state responses: threshold prediction using phase coherence
,”
Electroencephalogr. Clinical Neurophysiol.
67
,
260
270
.
52.
Supin
,
A. Y.
, and
Popov
,
V. V.
(
1995
). “
Envelope-following response and modulation transfer function in the dolphin’s auditory system
,”
Hear. Res.
92
,
38
46
.
53.
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
.
You do not currently have access to this content.