Time-frequency analysis of TEOAE signal

To obtain further understanding, TEOAEs of 30 normal bearing and 25 hearing impaired human subjects were recorded and analyzed with PC based system designed and installed in the authors' lab. The 3D visualized results of the time frequency analysis of TEOAE showed that the frequency components of normal hearing subjects mere uniquely related to the stimulating sound and individually showed different time pattern. Moderate hearing loss at certain frequency led to an intensity decrease at the similar frequency components of TEOAE. Severe hearing losses eliminate TEOAE. Early TEOAE might be produced before 3 ms, even as early as 1 ms. This implied that the olivo-cochlear bundle,vas not involved in the initiation control of TEOAE. By the research on the short time spectrum, time-frequency relations, and latencies of TEOAE, new approaches of revealing the mechanism of TEOAE call be reached.