Optical Illusions for the greater good – Perceptual Psychology

Take a look at the following perceptual illusion. And I guess I have to explain for the guys listening in the podcast. What you see here is the so-called Ebbinghaus illusion in which two centric circles can be seen. One is surrounded by smaller circles and the other one is surrounded by bigger circles. And even though both circles are exactly the same size, you get the impression I'm absolutely convinced that the circle which is surrounded by smaller circles seems bigger than the other one. And the reason for that is that we or that our brain always sees the world in relation to other things. So for example if you see a price in a shop and it's written that originally this tennis racket cost €399 but now it costs only €199. Now the price seems really small. So our brain is always putting things in perspective. And the interesting thing is that this can be used to influence behavior. So for example take the Ebbinghaus illusion. Scientists conducted several studies in which they told participants well here is a golf hole. Please try to put the ball into the golf hole. But one time the hole was surrounded by bigger circles and the other time it was surrounded by smaller circles. And it turned out that when it was surrounded by smaller circles which made the golf hole appear very big because of the Ebbinghaus illusion, people were much better at putting the ball into the hole. And the reason probably is that they felt more confident to do so because it all seemed more easy. Another very interesting and very important example is what the Chicago Transportation Center did at the very dangerous bend at which many car crashes had been. And they already had tried everything. They put up signs. They made the signs bigger. They put up lights. It all didn't really work. But one day they had a very interesting and clever idea. They started to make the distance between the middle lines smaller. And this created the illusion that when people were driving towards this bend and the lines became closer to each other, this created the illusion that you are driving very fast. Because as you know the faster you drive from a perceptual point of view, the smaller the difference between the lines becomes. And if you do this artificially by decreasing the distance between the lines, you can create the impression that you are driving very fast. And actually the results were quite impressive because in comparison to a six month period in the year before, the number of car crashes decreased for about 36 percent. And this is quite remarkable. And it shows us that perceptual psychology is not only interesting for wow effects that you say, wow, this is crazy what my brain does in this situation. But it can also be used for real life purposes. And I'm very curious to see which ways we can figure out in the future to apply more of this perceptual science to nudge people in a more safe or healthy direction. I hope you enjoyed this episode and if you want we'll see you next time.