The effect of level-ratio paradigm on DPOAE fine structure

• Published in: The Journal of the Acoustical Society of America Vol. 148; no. 4; p. 2467
• Main Authors: Scheidler, Samantha K., Norton, Mikayla, Naghibolhosseini, Maryam
• Format: Journal Article
• Language: English
• Published: 01-10-2020
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.5146822

Distortion product otoacoustic emissions (DPOAEs), sound signals recorded in the ear canal and generated inside the cochlea by presenting two primary tones (f1/L1 and f2/L2; f2 > f1) in the ear canal, can be used to study the health and function of the cochlea. Different primary tone level-ratioparadigms (L1:L2) can be used for obtaining DPOAEs and depending on the selected paradigm, different fine structure patterns are observed. The goal of this study is to understand how three common level-ratio paradigms affect DPOAE fine structure, generated by sweeping primary tones in frequency. The paradigms used are scissors, L1 = 0.4L2 + 39 dB; Boys Town “optimal,” L1 = 0.45L2 + 44 dB; and the equal-level, L1 = L2. The main components of the DPOAE signals, generator and reflection components, are extracted using a least squares fit algorithm. For each level paradigm, the phases of the generator and reflection components are used to determine the frequency distance between adjacent fine structure minima and maxima. This analysis is carried out for different primary levels and all paradigms. The interaction of the primary tones inside the cochlea and their impact on the fine structure pattern for each paradigm will be discussed.