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Volume 134, Issue 2, August 2013
- PHYSIOLOGICAL ACOUSTICS 
134(2013); http://dx.doi.org/10.1121/1.4812766View Description Hide Description
The present study evaluated the influence of suppressor frequency (f s) and level (L s) on stimulus-frequency otoacoustic emissions (SFOAEs) recorded using the amplitude-modulated (AM) suppressor technique described by Neely et al. [J. Acoust. Soc. Am. 118, 2124-2127 (2005a)]. Data were collected in normal-hearing subjects, with data collection occurring in two phases. In phase 1, SFOAEs were recorded with probe frequency (f p) = 1, 2, and 4 kHz and probe levels (L p) ranging from 0 to 60 dB sound pressure level (SPL). At each f p, L s ranged from L s = L p to L s = L p + 30 dB. Additionally, nine relationships between f s and f p were evaluated, ranging from f s/f p = 0.80 to f s/f p = 1.16. Results indicated that for low suppressor levels, suppressors higher in frequency than f p (f s > f p) resulted in higher AM-SFOAE levels than suppressors lower in frequency than f p (f s < f p). At higher suppressor levels, suppressors both higher and lower in frequency than f p produced similar AM-SFOAE levels, and, in many cases, low-frequency suppressors produced the largest response. Recommendations for stimulus parameters that maximize AM-SFOAE level were derived from these data. In phase 2, AM-SFOAEs were recorded using these parameters for f p = 0.7-8 kHz and L p = 20-60 dB SPL. Robust AM-SFOAE responses were recorded in this group of subjects using the parameters developed in phase 1.