Stimulus-frequency otoacoustic emissions measured with amplitude-modulated suppressor tones (L).
Stimulus-frequency otoacoustic emissions (SFOAEs) are typically derived as the difference in sound pressure in the ear canal with and without a suppressor tone added to the probe tone. A novel variation of this method applies a sinusoidal amplitude modulation (AM) to the suppressor tone, which causes the SFOAE to also be modulated. The AM-SFOAE can be separated from the probe frequency using spectral methods. AM-SFOAE measurements are described for four normal-hearing subjects using 6-Hz AM. Because the suppressor modulation is at a higher rate, the AM-SFOAE technique avoids the confounding influence of heartbeat, which also modulates the probe tone.
Neely
Stephen T
ST
Boys Town National Research Hospital, 555 North 30th Street, Omaha, Nebraska 68131, USA.
Johnson
Tiffany A
TA
Garner
Cassie A
CA
Gorga
Michael P
MP
D000161:Acoustic Stimulation; D016022:Case-Control Studies; D003051:Cochlea / Q000502:physiology*; D003638:Deafness / Q000503:physiopathology*; D006801:Humans; D008954:Models, Biological; D017084:Otoacoustic Emissions, Spontaneous