Flashing Lights In Eyes And Numb Hand


Hey, Vsauce Michael here, and todaywe are going to be talking about the past. But not like history—in fact—we willbe talking about what we call now. This very newest moment in time,and the fact that we can never really be aware of or livein what we call now, because it takes time for our brain to process the information aboutwhat's happening now, and it takes time for that informationto get from the rest of our body to our brain.

In fact, the taller you are, the further back from now, the furtherback from the past you live. But more importantly, why do we call emotional, relationshipbased movies targeted at femaleschick flicksé Well, for the answers to these questions, we're going to start with theflash lag effect. David Eagleman has done some amazingresearch on this effect.

It's what occurs when a participant looksat a ring moving around in a circle. A light is flashing exactly in the middleof the ring. This is exactly what the photons landingon their retinas represent. But when asked what they saw, participantsresponded they saw this. Now, for the longest time, it washypothesized that people said this because our brains guess ahead. Our brain assumed that the ringwould continue doing what it had been doing, and figured it would be safer to go aheadand say that the ring was already

a bit ahead of the light. But Eagleman wanted to know whatwould happen if when that flash of light occurred inthe middle of the ring, the ring all of a sudden reversed direction and spun around the other way. If our brains really are guessing ahead, participants should still say that they saw this,

because the brain figured that the ringwould be there and were surprised when it went the other direction. But instead, participantssaid that they saw this. Now, how could they have seen thisif they had no way of knowing that the ring was going to reverse directionéWere their brains clairvoyanté Can our brains see into the futureé As it turns out, no. What's really happening here is thatour eyeballs are receiving an image—

an image of a flash of lightinside a ring. But then our brains wait a little bit to make sure that we have the full story. And as the ring begins to reverse direction, that new information is incorporatedinto what we actually sense, and we become aware of the wrongversion of now. By doing more studies withrings traveling at different speeds, Eagleman was able to determine

Leave a Reply