Advances in voice recognition technology have seen it become a more viable form of computer interface, but it’s not necessarily a quieter one. To prevent the click-clacking of keyboards being replaced by noisy man-machine conversations, MIT researchers are developing a new system called AlterEgo that allows people to talk to computers without speaking and listen to them without using their ears.
At first glance, the AlterEgo headpiece looks like the product of a design student who didn’t pay attention in class. Instead of the familiar combination of an earpiece and microphone, the device is a cumbersome white plastic curve like the jawbone of some strange animal that hangs off the wearer’s ear and arcs over to touch the chin.
It might look strange, but it’s based on some fairly sophisticated technology. Inside the Alterego are electrodes that scan the jaw and face from neuromuscular signals produced when the wearer thinks about verbalizing words without actually speaking them aloud, a practice called subvocalization. This allows the headpiece to act as a microphone for a computer without actually picking up any sounds. Meanwhile, a pair of bone conduction headphones transmits sounds from the computer to the wearer that bypasses the usual channels and goes directly to the inner ear via the bones of the jaw and skull.