Dither no more (Image: Adam Hart-Davis/SPL)
WHY can’t teachers keep a secret? Because their pupils give them away. It turns out that when people make decisions, their pupils dilate, a subtle cue that could be used to predict a person’s intentions, or even converse with people with locked-in syndrome.
It is well known that pupils dilate as it gets darker, and in stressful situations as part of the “fight-or-flight” response. The reflex is mediated by the release of the hormone noradrenalin, which in animals has also been implicated in memory and decision-making. Olivia Carter, a neuroscientist at the University…
