Optical illusions are a topic of fascination to many people. The study of optical illusions has been a form of understanding how the brain and eyes work together in recent years for many neuroscientists. These optical illusions have been linked to brain malfunction–this happens when the human brain analyzes something and comes to the false conclusion that something is happening when it is not. Although there have been many studies on how the brain processes information it receives from the senses, there is no clear answer to how much of what the brain interprets is false and constitutes to this brain malfunction.
The process of the brain analyzing what the eyes see starts with rods and cones in back of the eye which create images of shapes and allows the brain to identify colors. The optic nerve then transmits this information to the brain, where the brain translates into a single image that the human brain perceives, or ‘sees’. David Cycleback explains that this singular image created with two eyes is known as binocular vision. With binocular vision comes a better depth perception because what is directly in front is seen with both eyes; therefore, having binocular vision creates a better image within the mind of the whole environment (Cycleback). This binocular vision dualed with a better idea of shapes and colors with rods and cones allows the human brain to be near perfect at processing information, or at least one would think.
According to Saul McLeod, by the brain processing information, although a sensation is accurate, the brain’s analyzation of the sensation may not be reality, such as seeing depth in a 3D drawing when there is no real depth (McLeod). This happens because binocular vision depth is easier to play on, as if something is closer or further than originally thought–an optical illusion. Yet, other times it is harder for the brain to know something is not there that it sees. The picture below from Ramon Bruin, an artist for 9 years, plays the brain in whether or not there is true depth. Because we know that paper is flat, the brain is not fully deceived. This is due to the body’s circuits. Everyone’s genes have circuits. As stated by Society for Neuroscience, these circuits in the brain are constantly being shaped by our environment and experiences (Society for Neuroscience). This means that the mind can create responses based off what it has processed from the image it created and past encounters with what the brain has analyzed (Goodale and Milner). Because the brain is creating thoughts and responses based on past experiences, the brain is able to understand and know that paper is two dimensional; therefore, anything drawn or written on the paper is two dimensional as well. This thought process happens almost instantly, possibly too quick.
Because the brain wants to analyze information as fast as possible, this allows the brain to get ahead of itself and predict wrong. Mark Changizi, a neurobiologist and assistant professor of cognitive science at Rensselaer Polytechnic Institute in Try, N.Y., has come up with a theory as to why we see illusions. He explains that illusions are due to the brain’s attempted to predict the future. These predictions occur during the slight time lag before the brain can process what the eyes are seeing. In this way, when the brain is attempting to generate a perception, the brain is simply taking a guess at the near future. Consequently, the brain may not be perceiving an image as it actually is, but rather how the brain expects it to be. This is showing that by the brain predicting what it is going to see before it actually sees it can constitute brain malfunction (Nierenberg). This false sense of reality can be tied to the fluency at which the human brain comprehends information.
Fluency, being defined in terms of the mind, is how information is presented or stated. Bob Nease, who received his doctorate from Stanford University studying methods to improve medical decisions, explains that if information is presented before the senses with fluency, the brain will process easier and view this information positively (Nease). For example, reducing salt intake has never been linked to prevent heart attacks or strokes and there has never been a known allergy to MSG. These are just some ways the brain is tricked into believing something that is not true. Between the brain predicting what it is about to see, and the brain holding onto beliefs of easier processed information, this may show why the brain believes in three dimensional images whether drawn or through virtual reality technology. These images both take advantage of binocular vision depth perception and rods and cones that makeout images in order to create a false analyzation of something being there when there is nothing.