The human brain still
baffles scientists.

The mysteries of the brain are a constant challenge. Scientists and philosophers have languished and pondered on this illusive grey organ for many centuries, poking and prodding, while trying to unravel its fascinating puzzle.

As time has passed, answers as to how the brain works, why it signals other parts of the body to function, how it’s chemistry rules our moods and the way it manages disease or injury, are slowly emerging. But there’s still a very long way to go as human’s have much to learn about this complex piece of biological engineering.

However, when the brain doesn’t work properly the suffering it can cause is devastating, not only for the sufferer but to those close to them. Not being able to speak properly, shake uncontrollably, lose your sense of reality and being paralysed are conditions no one wants to experience.

For people with neurological disorders such as Parkinson’s disease, Alzheimer's, depression and stroke, these types of symptoms are ones they have to deal with every day. And although there are many treatments that have positive effects, intervening in the brain’s signalling process could be the key.

This type of intervention may not be too far off. Exciting new research at the University of Queensland (UQ) is showing great promise for those who suffer daily symptoms like trembling, mood swings and other types of neurological dysfunction, and want to 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 a reasonably new intervention called 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.

This type of intervention 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 non-linear signal processing techniques, which are techniques of looking at highly complex behavioural systems, 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.

Dr Paul Meehan,
Mechanical engineer

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.

"Once the patient had performed the linguistic tasks set for them we then looked for differences and correlations in their brain activity depending on the outcome," Dr Meehan said.

"Our preliminary results were very interesting and showed discrimination between different linguistic tasks as well as a difference between left and right brain behaviour."

Dr Meehan said that the current progress of the surgery was very much dependent upon experimental research with no concrete indications as to why certain stimulants such as amplitude, frequency and waveform worked and others failed in certain patients.

"In addition, the success of the operation is strongly dependent upon the surgeons and neurologists interpretation of these brain signals and further insight here could provide better patient outcomes," he said.

Dr Meehan said the raw microelectrode data was complex and looked a bit like messy, 'noisy' signals.

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

"By using specialised non-linear and statistical mechanics techniques, our research indicates this so called 'noise' is integral to brain functioning."

"The key aspect of this research is that not only are we learning about the human brain we are also seeking to help people who previously couldn't be helped with other treatments."

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.