Put your waking cap on

Automatic alarms to wake drowsy pilots or drivers could be possible with remote brain-wave detection technology.

It could also make neurological research safer. The super-sensitive electronics can work 1cm above hair, its developers at Sussex University have claimed. Previously electrodes had to be stuck to the scalp or planted in the brain itself.

The technology, which could be fitted to a pilot’s helmet or driver’s headrest, can detect changes in activity levels in the brain. This would include reduced awareness when someone becomes drowsy.

The device could be used in an aircraft or car to trigger an alarm to keep an individual alert. Other potential applications include the control of machinery by thought power such as robotic aids, wheelchairs and video games.

Researchers at the university’s Centre for Physical Electronics in Brighton said the system works by detecting the brain’s electrical fields, allowing the possibility of non-invasive or remote monitoring. The normal method is to sense for a brain-wave’s electrical charge using electrodes.

Research leader Prof Terry Clark explained that the technology is designed to amplify the weak electrical field signals in order to read them.

‘We have improved commercial amplifiers a million fold. It works by feeding the output back into the input to enhance the otherwise very weak brain signal. This may stimulate new developments in real-time electrical imaging of the brain. We could even find ourselves controlling machinery with our thoughts alone.’

Traditionally doctors would have to stick up to 256 electrodes to the scalp. That involves shaving the patient’s hair and using skin abrasion before applying the electrodes. These require an electrically sensitive paste, made from silver chloride, to keep them in place and maintain a connection with the scalp.

But the paste often leaks away. In some situations the electrodes would have to be surgically inserted into the brain, a potentially dangerous operation. All this can be avoided with the remote method.

The new system was originally developed for heart signal detection – also created by the university’s electronics centre.

The electrical field signal from the heart is generated by the muscle’s electrochemically driven movement. Picked up by sensors, it is boosted by the sensitive electronics and looped to enhance the signal for analysis.

The system is now good enough to detect heart signals up to 1m away. Clark compared it to a gadget used in the science fiction series Star Trek to detect distant ‘life signs’.

But this system works only within the confines of a room that is shielded from other electronic signal sources, such as electric heaters, electrical motors and phones.

The next stage for Clark’s research is to find a way of imaging the heart’s electrical activity on a display. This will enable doctors to detect specific heart ailments without the need for surgery or other invasive procedures. Once that is achieved the team will aim to image brain activity.