December 13, 2004. Copyright 2004, Graphic News. All rights reserved

Scalp monitor could offer helping hand to paralysed individuals
By Mark Rutter

LONDON, December 13, Graphic News:  By recording brain activity through the scalp and transferring it to a computer, it may soon be possible to provide completely paralysed people with a means of carrying out basic tasks such as operating a light switch or a television set.

Many patients that are paralysed, for instance through spinal cord injury or diseases such as muscular dystrophy, can still produce movement commands in the brain. Nevertheless, they are unable to move because the route through the nerves to the muscles does not function. Scientists have for many years used computers to try to translate these electrical signals from the brain to instruct robots to carry out simple tasks, or to stimulate the muscles of a paralysed limb to allow movement.

Known as brain-computer interfaces, or BCIs, these techniques can involve implanting a device under the skull. Last month, American company Cyberkinetics announced that it had for the first time successfully implanted a small pill-size device into a human brain. Christened the ÒBrainGateÓ system, it allowed a quadriplegic to switch on lights, adjust the volume on a TV, change channels and read e-mail using only his brain.

The problem with ÒinvasiveÓ methods is that they are difficult to carry out and can be risky for the patient. For this reason, there is much interest in developing non-invasive techniques, which involve the patient wearing a simple cap. Although non-invasive techniques do not pose any danger to the individual, they tend to result in slow responses and to be suitable only for the most basic applications.

A new study, published in the journal Proceedings of the National Academy of Sciences, suggests this might be about to change. A team from the State University of New York believes that it has developed an improved non-invasive method that can provide control of complex movements of a mechanical arm at speeds achieved by natural movement. The study involved asking four adults, two with spinal cord injuries and two without disability, to move a cursor to a target area on a computer screen using only their thought processes. All of the test subjects completed the task successfully. Interestingly, the disabled individuals showed the better control.

This latest research, together with other recent studies, shows that by using a computer to interpret electrical signals passing through the scalp, it is possible to transmit commands to enable robots to carry out intricate tasks. However, Cyberkinetics, which is currently working on brain implants, argues that the only way to get a high level of detail from these signals is actually to carry out surgery to place a device on the brain. Despite this, the team from the State University of New York believes that its results are comparable with those of invasive methods, and offer great hope for improving the quality of life for paralysed individuals in the future.
/ENDS