Berlin Brain-Computer Interface

This is cool.

A computer controlled by the power of thought alone has been demonstrated at a major trade fair in Germany.
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The machine makes it possible to type messages onto a computer screen by mentally controlling the movement of a cursor. A user must wear a cap containing electrodes that measure electrical activity inside the brain, known as an electroencephalogram (EEG) signal, and imagine moving their left or right arm in order to manoeuvre the cursor around.
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Users can operate the device just 20 minutes after going through 150 cursor moves in their minds. This is because the device rapidly learns to recognise activity in the area of a person's motor cortex, the area of the brain associated with movement.