German researchers are developing a pacemaker for the brain to eliminate the uncontrollable trembling and muscle stiffness experienced by sufferers of Parkinson's disease, the incurable neurological disorder that affects four million people worldwide.
The disease, afflicting former boxer Muhammad Ali, actor Michael J Fox and the late Pope John Paul II, arises when information transfer is disturbed between brain nerve cells, which send out unco-ordinated signals instead.
"The brain pacemaker is an electrode that is implanted in certain parts of the brain and which is connected with cables under the skin to a battery and steering electronics," said Dr Peter Tass, researcher at the Juelich Research Centre at the University of Cologne.
The electronics generate a signal that suppresses the trademark Parkinson's tremor but, unlike similar devices already in use, its effectiveness doesn't diminish over time.
The new pacemaker fires up only when the nerves in the brain begin sending out their tremor-inducing signals.
"We need less electricity and achieve a significantly better effect as regards suppression of symptoms, the first study showed that," said Dr Tass.
In that test, a patient who had been unable to open her right hand for a year was able to use it again after 20 minutes of brain stimulation with the device.
Dr Tass, a physician and mathematical as well as a doctor, hopes to be able to draw up mathematical models to explain and predict the signal patterns and encourage greater co-operation of the rebel cells.
Already research has shown that the limited but better-targeted stimulation could help degenerating cells rediscover their normal rhythm on a long-term basis.
This stimulation of brain cells may also aid sufferers of other conditions such as multiple sclerosis, epilepsy, depression and stroke side effects.
Dr Tass said the device did not treat the condition itself, just the symptoms which become apparent when degenerating nerve cells produce decreasing amounts of dopamine, an important chemical messenger or neurotransmitter.
The brain loses its ability to control normal movements when levels of dopamine in the brain drop below 20 per cent of normal levels. The average age of diagnosis is 60 although one in 20 develop symptoms when under the age of 40.
The current version of the brain pacemaker is the size of a shoe box but by the time of its market introduction, hopefully in 2009, the device will be the size of a matchbox and small enough to implant under the collarbone.