In Macbeth, King Duncan once famously said "There is no art to find the minds construction in the face" researchers from Aberdeen University would have to respectfully disagree, as they have developed a method of determining mental illness, specifically schizophrenia, from a person's eyes.
It has been known for over a century that those with mental illnesses have impaired eye movements but until now it was believed that the differences were too small to be able to be used as a diagnostic metric. Those who suffer from schizophrenia have trouble staying focused on a single object, or smoothly tracking a slow moving object.
This is the first time the theory has been thoroughly tested, the result is a model based on a simple series of eye tracking tests, that report with a 98.3% accuracy rating to detect schizophrenia. The study took 88 people with the illness and 88 without as a control group, and mapping the differences until they achieved a model that separated the two groups completely.
Even with the high percentage it still isn't enough to be used as a primary identifier, with every 1 million cases 10,000 will get the bad news erroneously. That said it still has the potential to be a very useful tool in helping identify cases of mental illness. Further work the researchers are planning on doing is to try and use the technique to differentiate between mental illnesses like depression.
Source: Alpha Galileo Foundation