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Published on: October 11, 2010
Relationship between distortion product otoacoustic emissions and frequency modulation difference limens
1Department of Communication Disorders, Auburn University, Alabama 36849, USA.
Objective:
To explore the relationship between distortion product otoacoustic emissions (DPOAEs) and frequency modulation difference limens (FMDLs) in normal-hearing subjects.
Design:
Fifteen normal-hearing adult subjects (age range = 20 to 29 yr; mean age = 21 yr, 6 mo) participated in the study. Each subject met the following criteria: 1) hearing thresholds <20 dB HL bilaterally at frequencies 0.25 to 8 kHz; 2) type A tympanograms bilaterally; and 3) no history of otologic disease. To reduce gender-related differences, only female subjects were recruited as subjects. DPOAE amplitudes and FMDLs were measured in both ears of 15 female adults at 1, 2, and 4 kHz. Ears were classified on the basis of DPOAE amplitude into large DPOAEs and small DPOAEs.
Results:
Results indicated that ears with larger DPOAEs showed better frequency discrimination (smaller FMDLs) than did ears with smaller DPOAEs at 2 kHz.
Conclusions:
Results of the current study support frequency discrimination models that predict a relationship between frequency selectivity and frequency discrimination.
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