Ear's delicate coding mechanism

The ear works as an amplifier. We have been investigating its characteristics by using otoacoustic emissionsー “sounds from the ear”, and have revealed that the ear does not simply amplify sounds. Here we report our new finding that the ear translates sound intensity information into timing information of neural spikes. Prior to this finding, sound intensity information was believed to be expressed as the intensity of neural responses. Our finding questions the conventional belief about how we perceive the intensity of sounds, and it has significant implications on the disabilities caused by aging-related malfunctions of the ear. The study should also contribute to improving the performance of cochlear implants and hearing aids.?

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