Estimates of Cochlear Compression Using Distortion Product Otoacoustic Emissions and Growth of Forward Masking

Abstract

Objective: 

The authors investigated the relationship between behavioral and physiologic estimates of cochlear compression.

Design: 

Cochlear compression was estimated in distortion product otoacoustic emission (DPOAE) fine structure minima and maxima near 4 kHz. The composite DPOAE response and separated generator and reflection components yielded three estimates in four young adults with normal hearing. DPOAE estimates were compared to behavioral compression estimates derived using a growth of forward masking (GOFM) paradigm. The DPOAE primary tone f₂ and GOFM signal were identical and selected individually based on placement in a DPOAE fine structure minimum.

Results: 

Across participants, DPOAE compression estimates derived from the generator component were most similar to estimates derived from the GOFM paradigm and did not vary with DPOAE fine structure.

Conclusions: 

These results suggest that the generator component may provide a quick, reliable estimate of cochlear compression in humans. This may prove useful in populations that cannot give behavioral responses.

In Brief

This study investigated the relationship between behavioral and physiologic estimates of cochlear compression. Distortion product otoacoustic emission (DPOAE) estimates of compression were obtained in a DPOAE fine structure minimum near 4 kHz. The DPOAE composite, generator, and reflection responses yielded 3 estimates in 4 normal-hearing young adults. DPOAE estimates were compared to behavioral compression estimates obtained using growth of forward masking. DPOAE compression estimates derived from the generator component were most similar to behavioral compression estimates and did not vary with DPOAE fine structure. These results support the use of the generator component to measure cochlear compression.