Computer that reacts to thought a lifeline for brain injured

Nov 6 2008

People who have suffered traumatic brain injuries and who are unable to speak or move are being given the first chance to communicate using just the power of thought - and a laptop loaded with sophisticated algorithms.

The ground-breaking system has been devised by a computer researcher at the University of Portsmouth. Dr Paul Gnanayutham has devoted his life to giving people locked into silence after major brain injury the power to communicate but though his system works it will remain a lifeline for only a lucky few unless he wins funding.

The system he has devised uses patients' brain waves and eye and muscular movements (together called bio-potentials) to move a cursor on a computer. The targets a person can point the cursor at on the prototype device could include 'yes', 'no', 'thank you', a switch to turn on an electrical appliance such as a television, and a link to an internet page of the patient's choice, though the targets can be changed to anything a person prefers to say, or watch, or do.

This simple but life-changing breakthrough is not the first time scientists have found a way of using a person's brain waves to navigate a cursor but Dr Gnanayutham's is one of the first to be used on real people with serious brain injuries, rather than confined to a laboratory and tested on the able-bodied. All that is now needed for it to reach more people is funding to turn it into a product that can bought and used without expert help.

He said: "This technology has been around but very few people have used it for anything worthwhile, I worked with traumatic brain injured participants who were paraplegics, non-verbal and tube fed to give them a voice and the ability to say 'yes' or 'no' on a computer screen by using their bio-potentials.

"Learning how to navigate using their facial muscles or brainwaves isn't easy and can take months. I worked for eight months with one young man who hadn't communicated after his brain stem was broken in an accident. His mother knew he was 'there' and wasn't giving up on her son but there had been no sign, no movement, nothing until he started using the brain wave system.

"It turned out he was very angry - he didn't want his father to visit but had been unable to say so; his fiancée visited him but became increasingly distant as she went on with her life; only his mother and one nurse felt he was trying to communicate with them. It is the patience of very few people - those who really love or care for a person like this - who make the difference. If it hadn't been for the man's mother and one nurse who were sure he was trying to communicate he would have been ignored.

"Hospital staff look after these people - they feed them, wash them, shave them and so on but they do not have a voice. They have no way of saying 'actually don't turn off the lights please because I want to stay awake for another hour', or 'no, I don't want visitors today'."

But the breakthrough has other problems, he said, because many healthcare staff and even families of brain injured victims don't want the patient to be given a voice. It is easier to care for them and keep them fed and clean if they don't have the power to express a preference, to complain or ask for things to be done differently.

The system is non-invasive and works by attaching probes on an alice band worn around the head picking up brain waves (Electroencephalography or EEG), muscles (Electromyography or EEG) and eye movements (Electrooculorgraphy or EOG) signals at the forehead. These signals are then fed into an amplifier which can cut out external noise and listen only to the bio-potentials of the person wearing the electrodes and then to the serial port, so the computer just sees the brain-body interface as the cursor's control.

It cannot be used with patients who are heavily sedated but if a person can move their eyes left and right they can navigate a cursor on a computer left and right; if they can raise their eyebrows they can navigate a cursor to go up and down; and lastly, if they are taught to imagine their brainwaves can be 'read' by the computer they can learn to navigate the cursor through the power of their thought.

Dr Gnanayutham has seen people who haven't communicated with anyone for months or even years finally gain the power to 'speak'.

He said: "These people have thoughts and preferences and are the same as us in their heads and thoughts but they can't communicate. They can't tell anyone what they are thinking and are forced to watch the world but be locked away from it as well. Everything is working in their minds but they can't get it out. It is very frustrating for them and for those who love them and care for them.

"I have made it practical so it can be used by anyone. It is not for a laboratory experiment; it works for real people with locked in syndrome and gives them a voice."

Though the options for communicating are limited to a few simple words it is the first time such people have had any such options at all and their loved ones are able to be more outspoken in their gratitude.

"I have been thanked by parents and the husbands or wives of some people I have helped to whom a simple 'yes' or 'no' is the first conversation they have had with their loved one in years.

The research Dr Gnanayutham has carried out involves so many complicated permissions being obtained that much of his work was done abroad. In the UK if a patient is aged under 18 the parents can give permission for the system to be tried on their child but if they are over 18 it is almost impossible to get permission to try the system.

Dr Gnanayutham has just one body-brain interface machine and he lends it to people he has taught to use it for as long as he can before another patient's needs are greater. His dream is for the system to be developed so anyone could buy it off the shelf with an instruction manual. He said: "Many people are studying this in labs but nobody else is taking it to the people who really need it, they aren't going out into the field. I want people to be able to use it without doctors and without me. I want to give them their voice back. Only then will it be a real success."