Farwell and Donchin saw their "mental prosthesis" as a way to help people suffering from "locked-in syndrome" to summon caregivers or communicate their needs.
Intendix can also be used for this, but also for more frivolous purposes, such as social networking.
"We have an interface for Twitter," said Bruckner.
The company also demonstrated another interface that detects a different brainwave, the steady-state visually evoked potential (SSVEP). Four white LEDs on the interface pulse at different frequencies, and the system can use the frequency of the brainwave evoked to determine at which LED the user is staring.
In its demo, g.tec used the interface like a joystick to direct a robot to move forward, back, left or right, but the LEDs needn't be collocated, said Armin Schnürer, responsible for software engineering at g.tec. For example, he said, the LEDs could be placed on different objects around a room, such as a door opener or a light switch, allowing someone to control elements of their environment by looking at them.
Today, both systems use "wet" electrodes, which pick up the brainwaves using a conducting gel under the skullcap, but the company is working on a new version using dry electrodes, said Bruckner.
This is not the company's first trip to Cebit: In 2007 it displayed a brain interface the size of a shoebox that could be used to play the videogame Pong with a few hours' training, but the system on show this year is much more compact and quicker to use.
Cebit runs through Saturday at the fairgrounds in Hanover, Germany.
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