Distortion product otoacoustic emissions measured as vibration on the eardrum of human subjects.

ABSTRACT: It has previously not been possible to measure eardrum vibration of human subjects in the region of auditory threshold. It is proposed that such measurements should provide information about the status of the mechanical amplifier in the cochlea. It is this amplifier that is responsible for our extraordinary hearing sensitivity. Here, we present results from a laser Doppler vibrometer that we designed to noninvasively probe cochlear mechanics near auditory threshold. This device enables picometer-sized vibration measurements of the human eardrum in vivo. With this sensitivity, we found the eardrum frequency response to be linear down to at least a 20-dB sound pressure level (SPL). Nonlinear cochlear amplification was evaluated with the cubic distortion product of the otoacoustic emissions (

SUBMITTER: Dalhoff E 

PROVIDER: S-EPMC1780065 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature