When people make decisions, their pupils dilate, a cue that could be used to predict a person's intentions, says a new research.
It is already known that when it gets darker, pupils dilate. Such a reflex is mediated by the release of the hormone noradrenalin, reports New Scientist.
This hormone has also been implicated in memory and decision-making in animals. Now, Olivia Carter, a neuroscientist at the University of Melbourne in Australia, wondered if noradrenalin might also be linked to human cognition.
To solve the mystery, she and her colleagues asked volunteers to pick one of five random digits that displayed on a monitor one after another for 2 seconds each, and to press a button indicating their choice after the final number vanished.
As per an eye scanner's revelations volunteers' pupils were at their widest during the 2 seconds that corresponded to their eventual number choice.
The research team found that they could eventually predict with 62 to 100 per cent accuracy which of the five numbers people would choose, depending on the volunteer, based only on when their pupil dilated The study has been published in Frontiers in Human Neuroscience. (ANI)