Many of us, whether it has been during a psychology class or just from browsing the internet have come across a optical illusion. You may think that these illusions are purposely created to trick the human brain but really there are no tricks.

Try this illusion. Stare at the red dot in the middle of the circle for a minute or two. Soon the green circle will begin to disappear. Even when you look away from the image you continue to see the red dot in your visual field.  This is a static image file. Swiss physician and philosopher, Ignaz Paul Vital Troxler (1780–1866), came up with the concept “Troxler fading”, in which you become to accustomed to the green circle that you eventually stop noticing it is there. Troxler fading actually happens when you become dizzy.

The Visual Science, the Neural Correlate Society holds a contest where vision scientists share their latest optical illusions. This years winner was Mark Vergeer from KU Leuven (Belgium). His illusion “Splitting Colors”  is all about how we perceive colors. The illusion demonstrate that one and the same object can look different depending on its surroundings. In relation to Troxler fading, the different backgrounds change the way we view the two identical lines causing the viewers to be unable to see the original colors.

However, our perception of objects doesn’t solely rely on sight, other senses also come into play. Varun Sreenivasan from Switzerland, further examined the “rubber hand” effect. The idea concept is If your real hand is hidden behind a screen and you see a fake hand in its place, then you can “feel” it when a researcher touches the fake hand. During the experiment, one trial they asked volunteers to place one hand behind the screen. An experimenter would then scratch the table in front of the screen while either scratching or not scratching the hidden hand. The participants reported “feeling” a scratch on their real hand whether or not it was actually being scratched.

Illusions tell us a great deal about brain function. We are able to observe and experience different sensations due to our many different senses. Illusions conflict with our senses but by doing that it gives researches away to decode the brain works.