Have you ever tried looking at an image and getting confused because your eyes and mind seem to be playing tricks on you? Did you see something that others did not see? Have you felt being puzzled after looking at a picture that you just have to rub your eyes and look at it again? If you have encountered these things, you have experienced the wonders of optical illusions.
What are optical illusions? If we look at it literally, the word optical means something that is related to sight while illusion can be defined as a deceptive appearance or a wrongly perceived or image. It originated from the Latin word illudere which means “to mock” so, we can say that an optical illusion can mock you and reality.
Simply put, optical illusions are images that we perceive and see differently from what they really are. It is a visual stimuli which is seen through our eyes and then comprehended by our brains in such a way that is totally different from the visual reality.
When we look at optical illusions, what we see with our eyes are processed by our brains to give a perception which does not necessarily tally. Our brains can comprehend the image based on other images that we recognize or know. That is why, when two persons look at an optical illusion at the same time, what they see may not be the same and in fact, can be totally different from one another.
That said, optical illusions work differently on people. You might see images that other people cannot see and vice versa. However, that does not mean that you are better at seeing things and you should also not feel bad if you cannot see things that others can. Remember, it is all about personal perception.
Types of Optical Illusions
There are different types of optical illusions and these are the literal optical illusions, physiological illusions, and the cognitive illusions. Let us try to see the differences of each type.
Literal Optical Illusions
Often times, literal optical illusions are created by putting together different smaller images to make up a main image or a focal point. If you look at the image, you might be able to see the individual images easily, but when you try to look at them as one image, it might be totally different.
A great example of a literal optical illusion is the painting called “All is Vanity” which was done by Charles Allan Gilbert. The painting shows a woman seated in front of a vanity mirror which is in the shape of a circle. If you look at the whole painting, you might see an image of a skull, but there is actually none. The other objects in the painting only created that effect to give you an illusion.
You can say that an image is a literal optical illusion when you look at it and your brain tells you that what you are seeing is totally different from the other objects that make up the picture. You can even see an optical illusion in pictures or in real life, such as when you see images formed by clouds or by different items within your surroundings.
This type of illusion is usually the effect of excessive stimulation such as brightness, color, specific movement, or tilt. These illusions can cause you to see parts of an image which are not really there in the first place. What you can see are most likely the afterimages created by a stimulus such as a bright light.
Physiological illusions can also be the result of multiple copies of the image, creating a pattern. If you look at the repeating pattern, it will activate the same pathways in your visual system no matter where you focus your eyes on. The repetitive simulation creates a physiological imbalance which alters your perception and gives you the optical illusion.
One example of a physiological illusion is the Herman Grid Illusion. It is a very simple image of white lines and black boxes, but there is more to it than these two elements. When you look at the image, you can also see faint black dots where the white lines cross. The illusion was created through the contrast of colors and highlighted edges. The faint black dots or gray dots appear because of an inhibitory response which occurs due to the increased dark surround of the black boxes
Cognitive illusions are believed to be based on an individual’s assumption about the world. Each of us has different ways on how we perceive things based on our awareness and consciousness about different subjects. Cognitive illusions use these perceptions to create an optical illusion.
When we look at a cognitive illusion, instead of physically identifying an object, we tend to create different ideas and perceptions about it. We see an object which is based on prior knowledge of it or even assumptions.
A popular example of a cognitive illusion is the image called “My Wife and My Mother-in-Law”. Some people can only see a young woman looking away from the picture, wearing a thick coat and a veil or a fancy hat. Others can only see the side view of an old woman with a large nose, also wearing a thick coat and a veil or a fancy hat. There are also some who can see both images. It depends on what the brain sees, based on familiarity.
Furthermore, cognitive illusions can be classified into four categories: ambiguous illusions, distorting illusions, paradox illusions, and fictional illusions.
Optical illusions are fun and interesting. It is a great way to pass the time and test your visual skills and perceptions as well. You can try to look at different optical illusions online or even look for some around you. They can be found anywhere. They are not just illusions which can be used to trick your eyes or fool your brains, but they are also a great form of art. In fact, many artists, painters, and even filmmakers have been using optical illusions as a wonderful technique in their masterpieces.