National Physical Laboratory

Piezoelectric material to improve hearing

The spiral cochlea in the inner ear is a mechanical sound filter and frequency selector. Its thousands of sensory cells conduct electrical signals to the brain when stimulated by sound waves.

Mimicking the ear

Researchers at NPL, with support from the Institute of Nanotechnology and a Scottish Smart award, have made a prototype of a device that mimics the cochlea. Rather like the keys on a xylophone, the device can be tuned to respond to different sound frequencies.

It is made from a piezoelectric material, which produces an electrical signal when stimulated by mechanical resonance. The aim is to position the device along the right sensory cells in the ear and feed the signal down the auditory nerve into the brain.

Challenges include the need to maintain detectable frequencies at a microscale, and choosing a biocompatible material pliable enough to be moulded into the cochlea.

It is still some years away, but this pioneering work by materials scientists may yet make a difference to millions of deaf and hearing-impaired people.

For further information, contact Markys Cain

Find out more about NPL's research in Advanced Materials

Last Updated: 10 Jan 2013
Created: 11 Nov 2010