Document Type : Full Research Paper


1 Associate Professor, Physics and Biomedical Engineering Group, Research center of Sciences and Techonologin in Medicine, Medical Science University of Tehran

2 Post Doc. Researcher, Research center of Sciences and Technology in Medicine, Medical Science University of Tehran

3 PhD Candidate, Biomedical Engineering Group, Science and Research Branch, Islamic Azad University



An otoacoustic emission is a low-level acoustic signal which is generated in cochlea. It could be recorded with a sensitive probe in the outer ear canal. OAEs are considered to be related to the amplification function of the cochlea. Outer hair cells are the elements that enhance cochlear sensitivity and frequency selectivity and hence act as the energy sources for amplification. Otoacoustic emission is transmitted through oval window to the outer ear canal, the distortion effects of middle ear and outer ear on the recorded signal are inevitable. Currently all clinical applications of otoacoustic emission are based on distorted measurement. For estimating the original otoacoustic emission produced in cochlea the middle ear and the outer ear effects must be compensated. The computational model of the auditory periphery is used to design a compensation filter for the estimation of the otoacoustic emission right after production and before entering the middle ear. Using Middle ear reverse transfer function and primary input signal Fourier transforms, OAE estimation before middle ear was obtained. The results of comparison of the estimated signal with the recorded one indicate that, due to the noise reduction and increase in reproducibility as a main criteria in hearing screening, the assessment based on the estimated otoacoustic emission is closer to the real response of the auditory system.


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