About half of us can possibly see in the dark

By Casey Frye, CCNN Writer

see in darkness
Our brain recreates the illusion of our hand moving in the dark, even though we can’t see it with our actual eyes. It will even lock our eyes onto the illusion in a way that accurately reflects the reality of our hand’s location!

Have you ever found yourself in a pitch black room, unable to find the light switch? As your hands fumble pathetically along the wall, you could almost swear to see a shadow or outline of your own fingers. Don’t worry, you’re not imagining things. Well, not entirely at least. According to researchers from the University of Rochester, your eyes can “see” in the dark!

What is this, some undiscovered human ability for night vision? Sadly, it’s not. Apparently, our brain has so many memories of our hand, that it can trick our eyes into seeing what’s actually invisible. “Our brain predicts what we are about to see and generates an image accordingly,” said lead study author Duje Tadin, professor of cognitive sciences at the University of Rochester. To demonstrate this strange phenomenon, Tadin and his team ran several experiments on 129 participants.

In one of the experiments, the volunteers were exposed to 2 “different” blindfolds. They were told that one absolutely blocked out light while the other allowed a little bit to pass, when in reality, both made it impossible to see. Why trick the poor college students into thinking one of the blindfolds would let them see a little? Basically, it allowed researchers to have control over what the participants expected from the test.

Next, the students were asked to wave a hand in front of their face while wearing the cloth over their eyes and report what they did (or didn’t) see. According to the results, around 50% of them were able to “see” their own hand in the dark! “One thing our brains are exceptionally good at is picking up on reliable patterns,” said Tadin. “Think about how many times you moved your hand and saw that movement… It makes sense that our brains exploit this strong link.” For that reason, the participants could actually “see,” and the scientists are absolutely sure they weren’t lying, either. How, you ask?

Well, in other experiments, study volunteers were told to go in a room and wave their hands in front of their face. Since the room was pitch black (scary!), there was no need for a blindfold, which allowed for the use of eye-tracking technology. According to the results, the participants who could “see” their own hands moved their eyes extremely smoothly, which is impossible unless they are locked onto a target. It turns out, their brain accurately reconstructed what they would normally be seeing, even in the absence of actual visuals!

You can try this little experiment out for yourself. Hold a finger out in front of your face and watch it as it moves from left to right. Notice how your eyes move smoothly? Okay, now put your finger down and try to move your eyes from left to right again. Instead of a fluid roll, they bounce around from object to object, huh? This is why the scientists are sure participants weren’t lying!

Now, researchers plan on using this information to train people who have trouble with their hand-eye coordination.


Images courtesy of University of Rochester on YouTube.