Optical illusions are examples of challenges that we may face when trying to see the world around us as it is. They prove that sometimes we fail to see what is out there as it appears in reality. The causes of such failures are specific characteristics of our vision. In Riveted, Davies states that an important effect of optical illusions is that an illusion does not go away once a viewer understands that it is, in fact, an illusion, i.e. a deceptive impression. For example, when there are two lines drawn on a piece of paper with certain elements surrounding them, our eyes can perceive one of the lines as clearly longer than the other one despite their identical lengths. Even after measurements, when a viewer knows that the lines are equal, the optical illusion persists, i.e. one of the lines appears to be longer. This is the target example. In order to explain it, it is necessary to review certain aspects of human vision and perception.
First of all, understanding the phenomenon of optical illusions requires examining the general principle of how humans see things. There were two major theories: the extra mission theory and the intromission theory. According to the former, our eyes emit certain radiation that reaches things around us, gets reflected, and brings back the information on what those things look like (color, shape, size, distance, and so on). The latter, on the contrary, states that human eyes do not emit any radiation but only absorb light that comes from natural (the Sun, flame, lightings) or artificial (lamps) sources and gets reflected by various objects. The extra mission theory was proved to be wrong. Human eyes are devices that absorb light from external sources without emitting any individual radiation. Therefore, it can be said that the original input of human vision, which is reflected light, is the same to everyone who is looking at the same objects, not individual. However, vision is not merely about absorbing light; it is as well about processing it.
Processing of what we see occurs in the brain and depends on various complicated factors of specific characteristics of our brain and our previous experiences. For example, when a person who speaks English looks at an English text, he or she sees something meaningful, while a person who does not speak English and is not familiar with the Roman alphabet, sees random combinations of strokes, lines, dots, and curves. The reason for the difference of perception is that the former person learned what certain letters meant, i.e. how to pronounce them and how they compose words, while the latter person did not learn that. Similarly, when we see any object, our brain breaks it into elements, compares each one to existing patterns (i.e. to objects we are familiar with and have seen before), and tries to make sense of what we look at. This process is described by the Pandemonium Model of Perception. It can be said that although people look with their eyes, they actually see with their brains. Optical illusions may occur both due to the specific characteristics of how our eyes work and how our brain processes images, i.e. both when we look at things and when we see them.
Various studies have pursued an understanding of how optical illusions work. One of the main directions of the attempts to explain optical illusions is through gaining and developing patterns. Since our brain tries to make sense of what we look at by comparing it to what we have seen before, it can be argued that those who have not previously seen illusions or recognized them as such fail to acknowledge optical illusions, i.e. admit that they are, in fact, false representations. World-famous psychologist Alexander Luria stated that the ability to conceptually perceive optical illusions is linked to systematic education (Lamdan, 2013). Although the validity of his studies’ results was challenged by the modern-day academic community, some scientists still agree with the idea that illiterate people fail to admit the deceptiveness of optical illusions, e.g. that the lengths of two lines can be the same if they appear to be different to the eye. Luria’s studies bring an additional dimension to the phenomenon of human perception where images can be rationally recognized as false but not perceived as such nonetheless.
Another perspective on this phenomenon was described by Ross (2015) in a study of 3D cinema. The three-dimensional optical illusions are produced by projecting motion pictures on the screen in a special way and giving special eyewear to viewers. It creates an impression that a viewer can touch something that is on the screen because it appears to be within one’s reach. Although viewers clearly understand that the events of a movie are recorded and not unfolding right in front of them, they are still impressed because the way their eyes receive light in a 3D movie theater makes their brains perceive what they see on the screen as three-dimensional. It is enjoyable for viewers, which Ross (2015) finds a significant component of the illusion’s persistence. Optical illusions give people the feeling of an unreal experience, which is a pleasant feeling and thus a strong incentive for preserving the illusion.
Finally, it is recognized by scientists that optical illusions are not perceived in the same way by all people. An illusion for some is not an illusion for others. For example, there are optical illusions that are drawings or combinations of lines and shapes that can be perceived in two different ways, e.g. as a human face or as an animal. While most people after looking at the drawing for a while will be able to “switch,” i.e. to see it either as a face or an animal at a given moment, there will be a number of people who will only be able to see it as one of the options or, possibly, neither of the options (Madrigal, 2014). There are certain applications of how a person individually perceives a particular illusion. Therefore, optical illusions are not only entertaining. They can help researchers gain a better understanding of the visual perception mechanisms (Brown, 2016). Also, optical illusions can be applied to identifying and studying various brain disorders.
The target example was the optical illusions’ persistence in spite of the realization that they are deceptive. An attempt was made to explain the phenomenon through the base example of specific characteristics of human vision and perception of visual data. The results are that people perceive optical illusions differently and do not necessarily recognize them as illusions. However, if they do, their ability to know that an illusion is a false representation in spite of what their eyes see is associated with systematic patterns of perception. The persistence of illusions may be connected to the desire to have seemingly unreal experiences. In conclusion, the phenomenon of optical illusions vividly demonstrates the relevance of perception studies because it shows how things turn out to be very different in reality from the way we might see them right in front of us.
References
Brown, V. (2016). The reason why not everyone can see an optical illusion. Web.
Lamdan, E. (2013). Who had illusions? Alexander R. Luria’s Central Asian experiments on optical illusions. Dubna Psychological Journal, 3(1), 66-76.
Madrigal, A. (2014). Things you cannot unsee (and what they say about your brain). The Atlantic.
Ross, M. (2015). 3D cinema: Optical illusions and tactile experiences. New York, NY: Springer.