Now, spot the schizophrenics with a simple gaze

Impaired eye movement has long been thought to be associated with schizophrenia. Using 'simple viewing tests' demonstrated 98 per cent accuracy in distinguishing between those with and without schizophrenia.

Researchers at Aberdeen University explored the ability of eye movement tests to sort schizophrenics from healthy people, the 'Daily Mail' reported.

They found that people with schizophrenia showed well-documented deficits in the ability to track slow moving objects smoothly with their eyes.

Their eye movements tended to fall behind the moving object and then catch up again using rapid eye movements called 'saccades'.

Schizophrenics also found it more difficult to maintain a steady gaze.

The study was led by Dr Philip Benson and Professor David St Clair and involved a range of eye tests where volunteers were asked to track slow moving objects slowly with their eyes (known as smooth pursuit), inspect a variety of everyday scenes (free viewing) and given instructions to keep a steady gaze on a single unmoving target (fixation tasks).

Their findings could speed up detection of the condition and they are now examining whether the tests can be used for earlier intervention in major mental illness.

"It has been known for over a hundred years that individuals with psychotic illnesses have a variety of eye movement abnormalities, but until our study, using a novel battery of tests, no one thought the abnormalities were sensitive enough to be used as potential clinical diagnostic biomarkers," Benson said.

"In smooth pursuit, people with schizophrenia have well-documented deficits in the ability to track slow moving objects smoothly with their eyes. Their eye movements tend to fall behind the moving object and then catch up with the moving object using rapid eye movements called saccades," he said.

Several methods were used to model the data and the accuracy of each of the created algorithms was tested by using eye test data from another group of cases and controls.