16 July 2008

For sufferers of neurological disorders such as Parkinson’s disease daily trembling and shaking can be unbearable however, new UQ research could assist in helping patients regain control.

A team of UQ researchers is using their skills from across a number of different disciplines to help improve the success rate of Deep Brain Stimulation (DBS) surgery.

DBS surgery has been used in patients with neurological and movement disorders including Parkinson's disease, depression, dystonia, epilepsy, Tourette syndrome and recently Alzheimer's disease on an experimental basis.

It involves the placement of microelectrodes in problem brain cells, which transmit electrical impulses to correct the troubled area.

The electrodes are connected to a pacemaker-like device and for the surgery to be successful doctors have to pinpoint the problem area, guided by the conscious patient.

Through nonlinear signal processing techniques, UQ researchers have been able to interpret brain signals from the microelectrodes, directly implanted into the brain of Parkinson’s disease patients during the surgery.

Team member and mechanical engineer Dr Paul Meehan said simple linguistic tasks were given to the patient while awake during the surgery to directly monitor the human brain cells working in real time.

“We then look for differences and correlations in their brain activity depending on the outcome,” Dr Meehan said.

“Our preliminary results show discrimination between different linguistic tasks as well as between left and right brain behaviour.”

Dr Meehan said at present, the surgery’s progress was very much dependent upon experimental research with no concrete indications as to why certain stimulations such as amplitude, frequency and waveform worked and others failed in certain patients.

“Also the success of the operation is strongly dependent upon the surgeons and neurologists interpretation of these brain signals – further insight here could provide better patient outcomes,” he said.

Dr Meehan said the raw microelectrode data looked like messy, “noisy” signals.

“Previous research has filtered out this “noise” and therefore wiped out the correlations,” he said.

“By using specialised nonlinear and statistical mechanics techniques, our research indicates this so called “noise” is integral to brain functioning.

“So we are learning about the human brain as well as helping people who previously couldn’t be helped.”

The team involves Professor Helen Chenery, Director of the Centre for Research in Language Processing and Linguistics, electrical engineer and signal processing expert Dr Andrew Bradley, neurologist Professor Peter Silburn, neurosurgeon Dr Terry Coyne, PhD candidate Paul Bellette and PhD student Joanna Castner.

Both Dr Silburn and Dr Coyne are world leaders in the technique and are collaborating to provide data to further improve the surgery’s results and learn more about how the brain works.

Dr Meehan said the group was seeking funding to extend the research to investigate and understand different types of brain functioning and the development of optimised DBS tuning, microelectrodes and instrumentation.

Media: Dr Paul Meehan on 3365 4320 or Eliza Plant at UQ Communications (07 3365 2619, e.plant@uq.edu.au)