Understanding states of the brain


“Our model could show how sleep disorders arise and shed light on health and unhealthy brain behaviour...”

Professor Moira Steyn-Ross

The work of the University of Waikato's Cortical Modelling Group is helping the medical profession understand more about the brain.

Led by physicist Professor Moira Steyn-Ross, the team has developed a model that can predict how the brain will react in different states. They work closely with anaesthetist Professor Jamie Sleigh from the Clinical School at Waikato Hospital.

The group undertakes EEG simulation and modelling of anaesthesia, sleep and cognition.

For example, they can demonstrate the effect increasing or decreasing a drug dose will have on the brain, whether it will produce healthy or pathological results or perhaps cause a seizure. They are finding out how the brain works in conscious and unconscious states.

"Professor Sleigh was interested in knowing if the brain underwent a change of phase during general anaesthesia," says Professor Steyn-Ross. "Like the changes water undergoes when it's turned to ice, what we call a phase transition, and he called us in to assist."

The researchers found that the brain does indeed change when it becomes anaesthetised, and this unconscious phase is very similar to brain behaviour in the deepest phase of sleep.

By simulating the sleep cycle they are finding out how neurotransmitters affect the stages of sleep. "Our model could show how sleep disorders arise and shed light on healthy and unhealthy brain behaviour and what might be causing any changes. From there you can work out how to stop the brain going down a particular path."

Professor Steyn-Ross says their work is a marriage of biology and physics, a combination becoming more common in medical research. Associate Professor Alistair Steyn-Ross, also a physicist, does all the work on the computation side, and there's a lot of it; Physicist Dr Marcus Wilson works on the sleep project and Dr Logan Voss is a physiologist who works for the Waikato DHB and assists in the biological modelling.

The Cortical Modelling Group has won two Marsden grants administered by the Royal Society of New Zealand, in 2003 and 2007, and a Waikato Health Research Foundation grant, in 2008, to support its research.