It is well known that the eyes are said to be the windows to your soul. If you have seen a scary movie or action movie, you would have probably seen a scene showing the pupils of the actor dilating. Now, this is extremely common as the “Fight or flight” response in your nervous system dilates your pupils to allow more light in for faster processing of images. However, scientists have now found evidence that your eyes may be the window to your brain.
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When you and your friends internally self count a minute, do you both end at the same time? Usually, most people have a different perspective of time from one another. The amount of attention paid also affects whether you will overestimate or underestimate a second. But what if we tell you that we are able to know whether you overestimated or underestimated just based on the size of you pupils?
Scientists at the Hokkaido University School of Medicine in Japan have recently just found a connection between pupil size and whether you will over- or underestimate a second. Neuroscientist Masaki Tanaka of Hokkaido University School have demonstrated the negative correlation between pupil diameter and subjective passage of time through monkeys.
The study was conducted by training three Japanese Macaques Monkeys to internally count the time and then look at a specific spot on the computer precisely after one second. The pupil diameter of the monkeys were measured before and after the test. It was found the the pupil diameter was slightly larger for monkeys that have overestimated and smaller for monkeys that have underestimated. Meaning that for monkeys with larger pupil size, time passed by faster for them.
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Previous research has also shown direct relationship between pupil diameter and noradrenaline, a chemical messenger that functions in our brain and body. Noradrenergic neuronal activity (NNA) stimulates alertness in the brain which in result dilates our pupils. This allows us to understand exactly just how this phenomenon works!
Regardless of whether this study directly applies to humans or not, it is quite astonishing how we are able to see the monkeys’ internal stopwatch just by the size of their pupils! You can even try this at home to see whether or not you think it works on yourself or not!
Delia Ma
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