Neuro frontiers

Monday 3 February 2014 1:35pm

The future looks bright for the country's first academic neurosurgery unit at the University of Otago. It has been less than one year since the Neurological Foundation Professor of Neurosurgery, Dirk De Ridder, took up the newly-established chair after a public campaign to raise $3 million to fund the position in perpetuity, but already the unit is exploring new ground.

Comprising De Ridder, senior lecturer and UK neurosurgeon Mr Reuben Johnson, and neurosurgeon Mr Ahmad Taha, the unit's research is focused in two directions: basic science and neuroscience from a clinical point of view; and neuromodulation, or developing treatments for brain-related diseases. While both areas are distinct, each complements the other as the unit heads towards exciting new breakthroughs.

Furthermore, now the unit has three neurosurgeons, Taha has more time to undertake brain tumor-related research.

De Ridder, a world expert in the area of brain modulation (simply put, the different ways – invasive or non-invasive – you can change brain function), has already begun various research projects, collaborating with colleagues at Otago's Brain Health Research Centre.

"We are in the process of setting up a study in collaboration with Dr Nick Cutfield, from neurology, and Professor Cliff Abraham, from the centre, to investigate brain networks involved in minimal cognitive impairment, an early stage of Alzheimer's disease, with the hope of finding a potential target to prevent or slow down worsening of the disease," says De Ridder.

"We are also looking at a group of studies that aims to understand the mechanisms of the brain and how it learns new things. In a practical way, this is linked to addiction, particularly alcohol addiction and obesity."

"We are also looking at a group of studies that aims to understand the mechanisms of the brain and how it learns new things. In a practical way, this is linked to addiction, particularly alcohol addiction and obesity."

Working in parallel with extensive animal-based research conducted by Associate Professor John Reynolds, the group, which includes Medicine's Associate Professor Patrick Manning, has recently begun a human research project involving two groups – one with people in a healthy weight range, and the other with people who are clinically obese.

The project aims to explore the difference in brain activity between the two groups and how the brain "rewards" eating in the hope it will lead to new weight-loss treatments for obese people. The groups are initially tested, then again after being on a protein-rich diet. The expectation is that obese individuals will have different activity in their brain reward systems and not feel full as quickly.

"Normally when you have enough energy stored, your brain tells you it's had enough – and it does this by creating satiety, or the feeling of fullness. But what if this activity is not working normally?"

By gaining an understanding of this difference, the researchers could help discover new weight-loss treatments for obese people.

De Ridder says there are several treatment possibilities that could be developed including different forms of neuromodulation – such as the use of magnetic or electrical stimulation to replicate normal brain activity and the feeling of fullness, neurofeedback options, or a potential longer-term treatment may include a more invasive option such as neuroimplants or medication.

"Treatment is usually a three-phase approach. The first phase incorporates functional imaging with EEG, looking at what goes wrong in the brain, followed by phase two, which includes non-invasive neuromodulation – that is, trying to change this abnormal brain activity. In a third phase this is translated to a treatment, a longer-lasting change with normalisation of the symptoms."

With a worrying 27 per cent of New Zealanders obese (the 12th highest in the world) according to a report by the United Nations Food and Agricultural Organisation – and the associated health conditions and costs – De Ridder's latest research is crucial to the country's future health.

The unit is also collaborating with researchers in Antwerp (Belgium) and Dallas, Texas (US), in a series of studies that explore brain activity across a variety of conditions and the ways that neuromodulation may work better to treat these conditions.

"By understanding more fully the language that we use to talk to the brain, we are better able to imitate it. Neuromodulation is all about mimicking nature by replicating normal brain activity.

"The future looks very bright and interesting. Finally there is some translation of the Decade of the Brain*, with the data from animal research now translated to human research."

*  The 1990s were designated the Decade of the Brain in which there were great advancements in the understanding of the brain and the benefits of brain research.