How we respond to noise could be one of the key indicators of a predisposition to schizophrenia or Parkinson's disease according to the latest research underway at the University of Newcastle.

The researchers from the University's Priority Research Centre for Brain and Mental Health and Hunter Medical Research Institute (HMRI) are recruiting people for a study which will examine the relationship between these disorders and the way people process sound.

Project Manager, Dr Linda Campbell, said previous research had revealed that the brain chemical dopamine modulated how we responded to unexpected or suddenly occurring noises.

"Too much dopamine can cause psychosis and people can start to hear things no one else can hear, such as voices," she said.

"People with schizophrenia have been found to have too much dopamine, and medication to block dopamine action in the brain is one way of controlling aspects of the disorder. But people with Parkinson's disease have too little dopamine, which creates movement problems."

"However, when treated with medication to increase dopamine in the brain, Parkinson's patients sometimes become psychotic, while people with schizophrenia have the reverse effect and sometimes experience movement problems, similar to Parkinson's disease."

Dr Campbell said this posed a great challenge to the treatment of both disorders.

"This study into this emerging area will examine how, why and where differences in dopamine-related behaviour arise in the brain while listening to sounds," she said.

The University's Priority Research Centres bring together researchers across health, energy and the environment, and science and engineering. This study has received funding from the National Health and Medical Research Council.

Researchers are inviting people to participate in the research which will involve an interview, a hearing test, an EEG recording which picks up the subtle electrical activity of the brain, and a magnetic resonance scan of the head (MRI). People with and without schizophrenia or Parkinson's disease wanting to find out more about the study can contact the study recruitment officer, Vanessa Case, on 02 4924 6603.

Project Manager, Dr Linda Campbell is available for media interviews today (Thursday 8 March 2007) and is contactable via Kate Reid. A photo opportunity is available between 11am and 1pm today.