Spector, a reconstructive surgeon, is focusing on children born without a fully developed external ear, a condition called microtia.

WSJ: Scientists use 3-D printing to help grow an ear

Conductive hearing loss can often be caused by malformations of the external or middle ear or by severe middle ear infections.

BBC: bonebridge

Her ear provided external judgment.

NEWYORKER: Personal Best

The engineers found a way to kick-start a radio-frequency device wirelessly using an external power source initially, but running the device afterward on the output of power generated by the inner ear.

WSJ: Harnessing Energy From the Body to Power Devices