Asking patients to play a simple computer game could reduce the misdiagnosis of mental health disorders like bipolar and depression by as much as 49 per cent.

The game is similar to two-up. It asks patients to select one of two coloured boxes and the player is rewarded randomly each time based on their choice.

Where a healthy patient would likely choose the same colour until they are rewarded, those with bipolar switch between the two, explains lead researcher and neuroscientist Dr Amir Dezfouli.

"The idea is that different psychotic disorders affect the brain's decision making system in different ways," he said.