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Do you see black dots?. Optical illusions. Does it look like its moving?. By Peggy and Anastasia. What is an optical illusion?.

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Optical illusions

Do you see black dots?

Optical illusions

Does it look like its moving?

By Peggy and Anastasia

What is an optical illusion
What is an optical illusion?

An Optical Illusion is an object causing a false visual impression. Like this one for example, it looks like there is a white triangle but it is just a blank space, three V’s and three packman shapes.

Movement of still objects
Movement of still objects

When you look at a still circular object or a spiral, it might appear to be moving, but actually, the brain is just playing tricks on you.

This happens because in the visual nervous system there are some cells that respond to specific directions of motion. For example, when a person looks at an object moving upward, such as a fire the persons upward receptors are moving in action. So if the person is looking at this fire for long enough for the cells to become tiered, then looks at a still and simple object such as a building, the building will appear to be moving upwards.


If you look at the box closely, you can see some grey spots at the corners of the boxes. This happens because the contrast is so high that some of your cells in the retina shut down. So the blocking causes the grey spots to appear.



Escher s waterfall
Escher’s Waterfall

In this illusion the water seems to be moving up. But, gravity says different. The effect of this illusion is generated by conflicting proportions which create a visual paradox. We usually find geometric pictures which are usually informed as brain puzzles or tasks, rather than art.

Negative illusions
Negative Illusions

After staring at the dot for about 25 seconds the bright colors of the rainbow make your retina be exhausted so the photo respirators stop functioning properly. When the main image appears they have to fit in the new image so they will not be able to perceive the new colors. Now the excited photo receptors are now resting so the ones that were not exited are doing the job. This time the colors are in this original image, but change because this time the brain cells interpret colors in a different way.

More illusions
More illusions!



For our information:

http://www.pbs.org/wnet/brain/illusions/color.html http://www.weirdoptics.com/eschers-waterfall-illusion/

For our pictures:


For our video http://www.youtube.com/watch?v=p26nNgWAleI&feature=related

For the other illusions: http://kids.niehs.nih.gov/games/illusions/lots_of_illusions.htm