According to the New Scientist which is publishing the story next week, the prototype gadget is called Finger Whisper.
It consists of a wristband that converts digital signals into vibrations that are transmitted into the bones of the hand.
The user puts his finger into his ear for the vibrations to be picked up by the eardrum, which then transcribes them back into sound signals for the brain.
To talk, he or she simply speaks into a microphone on the wristband.
By touching forefinger to thumb, the user starts or ends a call, and uses voice recognition technology to dial the number. There is no keypad.
Japanese telecommunications giant NTT DoCoMo is developing the idea, which is the brainchild of a research engineer, Masaaki Fukumoto.