Central Nervous System (CNS) disorders such as depression, schizophrenia and Attention Deficit Hyperactivity Disorder (ADHD) cost upwards of US$2 trillion globally every year and affect one in four people in their lifetime. At present, diagnosing these conditions relies on a process of questions and interviews with the patient, which means it can take many years for sufferers to be correctly diagnosed. A new diagnostic technique that measures the patterns of electrical activity in the brain's vestibular (or balance) system could dramatically fast-track the detection of mental and neurological illnesses.

Monash University, Melbourne, Australia, biomedical engineer Brian Lithgow saw the diagnostic potential of measuring and comparing different patterns of electrovestibular activity because the brain's vestibular system is closely connected to the primitive regions of the brain that relate to emotions and behavior. By measuring the patterns of electrical activity in the brain's vestibular against distinct response patterns found in depression, schizophrenia and other CNS disorders, Lithgow was able to develop electrovestibulography, which is something akin to an "ECG for the mind".

Working with psychiatry researchers at Monash University's Alfred Psychiatry Research Centre (MAPrc), he tested volunteers and found distinct response patterns, or "biomarkers", that distinguished different CNS diseases from each other and from regular electrovestibular activity.

The university has teamed up with corporate partner Neural Diagnostics to develop and patent electrovestibulography, or EVestG™. It is hoped the simple, quick and inexpensive screening process for CNS diseases will eventually become standard practice in hospitals around the world.

"The patient sits in a specially-designed tilt chair that triggers electrical responses in their balance system. A gel-tipped electrode placed in the individual's ear canal silences interfering noise so that these meaningful electrical responses are captured and recorded," the Monash researcher said. "The responses are then compared to the distinct biomarkers indicative of particular CNS disorders, allowing diagnosis to be made in under an hour."

The Monash University researchers say the technique is already attracting international interest and, if further testing goes to plan, it could be adopted in Australian and overseas hospitals within a few years.