With careful training a person can send nerve signals to their vocal cords without making a sound. These signals are picked up by the neckband and relayed wirelessly to a computer that converts them into words spoken by a computerized voice.

A video shows the system being used to place the first public voiceless phone call on stage at a recent conference held by microchip manufacturer Texas Instruments. Michael Callahan, co-founder of Ambient Corporation, which developed the neckband, demonstrates the device, called the Audeo.