One wonders what an optical illusion is
One wonders what an optical illusion is, “an optical illusion is a visually perceived image that differs from reality.” (Eifrig, 2014, n.p.). There are so many different types of optical illusions in which play with the brains of people. Optical illusions are normal because the majority of humans experience them. Humans’ vision tries its best to figure out what is happening to the picture, which then creates an image contradicting reality. Sometimes illusions can be entertaining because it fools the brain and one tries to figure out the image shown. Illusions cannot only be in a form of art but sometimes it happens whenever reading something without putting much effort.
Optical illusions are images that contradict real life. Meaning that the image created is not really the way it might appear. “Optical illusion can use color, light and patterns to create images that can be deceptive or misleading to our brains” (1) (“Optical illusions”, n.d., n.p). Although the brain is, quite an important part, images can still fool it. Some people might think that it is incorrect to experience illusions but it is normal for optical illusions to occur. A person may think that is it only one that senses illusions but in fact everyone experiences optical illusions.
In order for an illusion to occur, it first gathers information through the eye, and then the brain processes it, which then creates an image. The image that the brain comes up with is on two different perceptions of the image and then ends up creating an image opposing reality and does not match actuality. This is all based on two different perceptions that are made by our eyes and brain. Perception is the analysis taken by the sense of a person. “Optical illusions occur because our brain is trying to interpret what we see and make sense of the world around us.”(2)(“Optical illusions”, n.d., n.p). Illusions are misled human brains into seeing things that are not real. In figure 2, the apple is not in circled in an orange circle looks like an apple, but if it is surrounded by the orange circle the eye creates an orange.
Perception is quite an important piece in real life as well. The power of perceptions is amazing how it can actually help one or bring one down. One has the power to determine the response from events. “Perceptions begin when the human brain receives data from the body’s five sense.” (Enayati, A., 2012, p.2). An example that demonstrates how perception is able to help is Victor Frankl, a Jewish psychiatrist who lived three years in a Nazi concentration camp during World War II. Frankl became aware that he had only one freedom during that time which was the freedom to determine his response for a sorrowful truth. To imagine is to have the power to decide the response to events. Frankl decided that he would image seeing his wife, teaching students about what happened during the Holocaust, and the lessons learned while being in camp.
Ludimar Hermann developed the Hermann Grid in 1870. The grid consists of black squares in which are in a grid, with white bars separating the black squares. “The fuzzy dot that appears at the intersections of the bars is called an illusionary dot.” (Blatchey, Moses, 2012, p.257). Humans are most likely to see the fuzzy dot in lower saturation of color; color and saturation affect the perception of the fuzzy illusionary dot. The Scintillating Grid is the modern version of the Hermann Grid. This grid uses special mechanisms that are in the brain and eyes. These special mechanisms help humans see edges clearly, as well as seeing a boundary between the background and an object. Lateral inhibitions are the mechanisms for creating sharp edges. “It works by the light-sensitive receptors in your eye switching their neighboring receptors off.” (2)(“Optical Illusions”, n.d, n.p). The black dot created in the grid has to do with lateral inhibition.
Motion aftereffect (MAE) is an incredible image, also known as the waterfall illusion. Motion aftereffects make patterns look as if it is moving the opposite direction. The waterfall illusion can be expressed in several ways depending on the structure of the display. For example, “large field spiral patterns yield MEAs.” (Wade, Zeife, 2008, n.p). The cells responsible for signaling motion become tire while staring at the spiral moving, which then create this illusion. The cells responsible are in the brain. There are different types of cells that notice movement in different directions in the brain. For instance, the cells responsible for signaling clockwise rotations become tire, and then the anti-clockwise cells send signals, which cause them to create an illusion.
There are times in which people experience illusions without knowing that they might be. An example of an illusion that the majority of humans experience is mirage. Mirage is objects that are far away seem closer than they actually are, or sometimes-tall buildings or mountains seem to float in the sky. There are different types of mirages but the most common mirage is oasis. The bending of light rays (refraction) and different temperature cause mirage to occur. Light refraction is the change in direction of a propagating wave of sound or light when passing from one medium to another. Mirage occurs whenever there is “a difference in air density caused by a difference in air temperature,” (“What is a mirage?”, n.d, n.p). This type of illusion is extremely common in hot areas, but it can occur in icy areas, in this case, mirage looks higher than usual. Even though there are, different types of mirages light bounces toward the eyes in different angles that make people think the image is mirrored.
The perspective of an image is extremely important whenever creating an illusion. Perspective is a technique used by artist to create an illusion of distance and depth. Majority of the people who see perspective believe to be looking through a window. From the side of the picture it is a “window frame” making distance look reduced from the window. Perspective became an interest once again during the Renaissance paintings in the 1400’s and 1500’s. Greece and Rome where the first to understand aerial and linear perspectives and was then abandoned during the Middle Ages (400 A.D.) There are two types of perspectives in which are aerial and linear. Aerial perspective is, “based on light, shade, and color change with an object’s distance from viewer.” (Edgerton, 2013, n.p.). Linear perspective is the technique to show distance and depth through the form, size, and positions of objects.
Impossible geometry is a two-dimensional image, but the brain thinks it is a three-dimensional object. For some reason the brain tries to instantly create, a three-dimensional image but fails to figure it out. For humans, the visual system makes assumptions based on images seen before. An example of an impossible geometry is the impossible triangle, trident, or cube. The triangle will look as if it would be flat on a table, and then part of the triangle begins to stick out. The point of the impossible trident is to be able to create a cylinder using two lines and a rectangle using three lines.
Overall, illusions can be extremely deceiving. The brain of most humans is not really suppose to see things how they actually are but create the closest image possible. Optical illusions are a way to manipulate the human brain and tricking it into seeing things that are not there. The brain and eyes are what creates illusions because of perception. Although it might not seem logical but optical illusions can help the brain become smarter in a way so it cannot be extremely gullible.