Think it, and the computer will do it. This ultimate melding of mind-and-machine is closer than you might suppose, yet will have to overcome some potential show-stoppers before ever becoming fast enough or commonplace.

Known as a brain-computer interface (BCI), the method translates the electrical impulses of neurons to actions on a computer screen or mechanical device.

As with voice recognition, BCIs have arisen to help those with injuries or debilitating ailments, such as brain stem strokes or amyotrophic lateral sclerosis, often called Lou Gehrig's disease. Over the past decade, BCIs have enabled human patients who cannot move their bodies to move a cursor on a monitor.

A long-recognized problem in developing commercial BCIs for healthy people is that getting a strong, clear enough signal from the brain requires implanting electrodes that are prone to infection, bodily rejection and forming of scar tissue.

However, other existing, non-invasive brain scan technologies such as electroencephalography (EEG) – worn shower-cap style with electrodes on the scalp – have made some strides recently.

At the CeBIT tradeshow in Germany earlier this month, Guger Technologies showed off the Intendix device, which the company calls the “world’s first BCI speller.” Letters and numbers on a virtual keyboard flash on the monitor, and when the one you want lights up, Intendix registers a slight spike in brain activity and presto, the character is selected.

The company says Intendix will let injured or ill people communicate, and that learning how to use the Intendix interface takes mere minutes to produce a character rate of five to 10 per minute. This is clearly too slow for everyday use by healthy people, and another disadvantage is that the device cost $12,000.

Down the road, continuing research into "neural prosthetics" – devices connected to people's brains and operated by brain waves – may pave the way for possible desktop adoption.

Whatever the future might hold for human-computer interfaces , it seems that the mouse's days as a humble, steady workhorse appear just as numbered as those of the horse-and-buggy of yesteryear.

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