Perceptual Illusion:

Muller Lyer Illusion

Muller Lyer Illusion is a visual illusion that involves arrows. It was devised by Franz Carl Muller-Lyer in 1889. The illusion is about our wrong judgements on the length of lines. Lines with arrows pointing outwards are usually considered shorter than those with arrows pointing inwards. The explanation for this effect is related to our 3-dimentional space perception. How human beings perceive the distance, the 3D relationship between objects are mostly based on the relative sizes of those objects. Our minds will take depth cues on the lines and then project different lines into different places in our in-mind 3d models. For viewers, the angles pointing inwards are usually considered as closer. Therefore, those lines, from people's point of views, are "actually" shorter because they appear as the same length.  As for drawing, if artists paint different objects with different size and different angles, artists can create the effects that objects on the painting are of different distances from viewers, even though those painted objects are on the same platform-the painting.

Mass Effect

The first example is related to clothing. From Morikawa, K.'s article we can see that high-cut bathing suits can make leg appear longer because there is an outward arrow on the edge of the suit(Last but not least: An application of the Müller-Lyer Illusion. Perception, 32(1), 121- 123).
  

The second example is related to soccer. Actually, goal keepers can save penalty kicks by applying Muller Lyer Illusion. If the goal keeper does a gesture "arms down", the penalty taker will perceive goal keeper smaller than he actually is. Thus, they will kick the ball lower than it should be and thus, the goal keeper can make the soccer closer to him.

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Media/Art

The first example is about paintings. Muller-Lyer illusion is actually everywhere in art pieces. Though artists rarely create specifically using Muller-Lyer illusion, basically all paintings concerning 3D spaces are related to Muller-Lyer illusion. Paintings are just a plat 2 dimensional presentation, but because artists paint objects with different sizes and have different cues indicate their different distance from us, our brains are "fooled" by those Muller-Lyer illusion tricks used by artists and incorrectly perceive paintings as a 3 dimensional space.

The second example is in architecture. We can see in architects' design drawings they use outward and inward arrows to present lines in different distances. As we can see, in the following picture the two lines are drawn to create a sense of 3 dimensional space.

Reflection

From this project, I learned that illusions can be applied in many different ways. Even some small tricks can make big difference. For example, the we can crate great illusions just by slightly changing the angles of arrows. Our brains are much more easier to be fooled than I used to think. Also, it's quite interesting to think that all the images we perceived, in some way,are just made up by our brains. Thus, we can make up some illusions, some non-existed messages and convey them to viewers in a believable way by applying those illusion tricks. What we think we see are just thoughts and we can modify those thoughts instead of modifying real life objects. As media designers, we can totally create those excitement, specific feelings to people. Later on, when creating some paintings or media, I will think more about its effect directly on human brains and consider more about how viewers perceive media, not just how viewers see media.