Electrodes are places into the brain to help ease symptoms
New ways of treating Parkinson's disease by stimulating the brain are to be investigated by scientists.
Deep brain stimulation eases symptoms, such as tremors, by allowing sufferers to deliver electrical pulses to electrodes implanted in their brains.
Researchers at St Andrews University will study what happens in the head when the electrodes are switched on.
They will also look at whether other symptoms can be eased by targeting different parts of the brain.
Symptoms of Parkinson's disease include tremors, difficulty moving and poor balance.
Professor Philip Winn, from St Andrews University, will work with researchers in Germany, Italy, France and Scotland on the three-year, £1.17m project.
He said he wanted to find answers to a range of questions.
"One is to do with exactly what effect the electrical stimulation is having on the brain.
"Is it the case that we're stimulating activity or is it in fact the case that the stimulation we do, what the electrical pulses do, is actually to shut down activity locally where the electrode is implanted?" Prof Winn said.
He said more effective treatment for Parkinson's could be developed if they could understand the effect of the stimulation.
The other part of the research will consider where in the brain the electrodes should be placed.
Prof Winn said: "If you put the electrode at the most commonly used site you can inhibit tremors that Parkinsonian patients have, which are very disturbing and distressing to them.
"But it's thought possible that if we put electrodes at other sites we can have an affect on the posture and gait problems that patients have.
"These are quite difficult problems for patients because they can lead to falls very easily in elderly patients."
Prof Winn believes deep brain stimulation is particularly useful in cases where drug treatments are proving ineffective.
He said: "The average age of onset for Parkinson's is round about 61 and at that point you can do quite a lot with drug treatments but as patients get older then the drug treatments tend to have less effect.
"But with deep brain stimulation - the electrical stimulation technique - you can prolong quality of life quite significantly."