Cognitive straightening: a session of illusions with full exposure

In the illustration above, you see a diagram of cognitive distortions — systematic deviations in the perception of reality. You can see the full version of the picture in Russian here , and this link will find the original data in JSON-format. 175 fascinating cognitive bugs appeared not from scratch - everyone has a root cause, although in some cases scientists have not fully determined the source of the perception error.

Usually, a distortion is preceded by an overabundance of information, difficulty in understanding, the need for a quick response or restriction of our memory. But the most common cause is the peculiarities of human thinking. One of the most interesting types of errors is optical illusions. Today we’ll talk about this, because visual illusions best demonstrate ways of creating a sense of reality within the brain. By studying these mechanisms, we have a better understanding of how to make an indistinguishable from the physical virtual world.

Wild, wild world

From the point of view of evolution, all the most interesting things happened to the brain yesterday. While you are sitting in the office, the neurons are not asleep and are ready to send the body on a journey - away from the saber-toothed tiger, cunningly jumping from the top of a boulder.
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Neuroscientist Bo Lotto argues that in reality we do not see reality, and our senses, designed to help us understand the world around us, impede its objective perception. To illustrate this thought, he proposed the following drawing.



The square on the upper edge seems to us dark brown, on the side - more bright - brown-orange. However, this is just an illusion created by our brain. In reality, the cube looks different.



How is this possible? In very low light individual colors are indistinguishable. From the point of view of survival, such a state of reality is destructive, since a predator hiding in the gloom can pounce on a person. And then a “perception error” comes to the rescue: an image is formed on the retina that is different from the object that created it.

For example, in the evening forest we perceive the movement of the bushes as a living object. And only after looking closer, we understand that in reality these are branches stirring from the light breeze. The brain was wrong, but evolutionary mechanics “hit or run” is more beneficial than the “stand up and analyze” reaction. It is better to mistakenly see different colors, movements and threats than to be eaten once.

The illusion of Muller-Lyer: a classic deception

The German psychiatrist Franz Karl Muller-Layer in 1889 showed a geometrical-optical illusion associated with the distortion of the perception of lines and shapes. The illusion of Muller-Layer is that the segment framed with tips facing outwards appears shorter than the segment framed by “tails,” in fact, the length of both segments is the same.

The psychiatrist also drew attention to the fact that the contemplative of the illusion, even after measuring the lines and listening to an explanation of the neurological background of the image, continues to consider one line shorter than the other. It is also interesting that this illusion does not look the same for everyone and there are people less susceptible to it.

Attempts were made to explain the principle of the Muller-Lyer illusion:

• “Wrong size”: the image of the arrowheads falls on the part of the visual system in the retina, which is responsible for processing the image depth signals. As a result, the line with the tips directed inward is interpreted as longer because it is perceived by the retina as being farther away;
  
• "Conflicting signals": arrowheads are perceived as a contribution to the length of the line, respectively, the longer overall line shape with the tips pointing inward causes the effect of increasing the length of the line;
  
• “Confusion”: the distance between the tips affects the perceived length. So, for a line with tips facing outward, the distance between the tips of the arrows seems to be less than the distance between the tips of the arrows directed inward on a different line.
  

We still do not know the correct answer, so you can offer your version or support one of the existing ones. In any case, the work of Muller-Lyer made a great contribution to the development of cognitive science. It became clear that the mind is a far from perfect mechanism, which can make mistakes even when working with accurate, at first glance, complete information, cleared of the influence of emotions.

The brain processes information in a series of interconnected modules, and one module may be unaware of the existence of another. Some modules are a kind of semi-independent sections of consciousness, dealing with certain types of input data and giving certain types of output data. Their inner work is not accessible to human awareness - everything that we can access is the result of the work of hidden internal systems.



The illusion of Müller-Lyer shows that some module continues to show us different lengths of lines, despite the understanding that this is wrong. Another well-known illusion of this kind is called vertical-horizontal. In the figure above, the vertical line appears longer than the horizontal, but in reality they are equal.


With the dynamic illusion of Muller-Lyer it seems to us that the animated arrows change the length of the lines, but in fact it remains the same.

Pinna-Brelshtaff Illusion: Brain Bugs

In 1990, thanks to the work of Bainio Pinna (University of Sassari, Italy), the first visual illusion appeared, demonstrating the effect of rotating motion. In its present form, the illusion was presented in 2000 in a joint article by Bainio Pinna and the English psychologist Gavin Brelshtaff.

Pinna-Brelshtaffa illusion consists of several concentric rings consisting of small diamond-shaped elements arranged at an angle, in different directions in the inner and outer rings. Depending on whether you are approaching or moving away from the image, the circles turn in different directions. But such an illusion will disappear if the rhombuses are not inclined.

When you approach the monitor, the circles on the screen should become larger for your brain, but the neurons responsible for detecting movement “tell a lie” and create an illusion. It is believed that the illusion is caused by the "bugs" of the neurons of the visual cortex. When looking at a static picture, the neurons of this area need 15 milliseconds more time to activate than with the usual perception of real complex movement.

Scientists believe that understanding the mechanics of motion perception will help avoid situations in which it is dangerous to stimulate a movement-sensitive area in the cerebral cortex. So, the wrong visual content on the dashboards of cars, airplanes and other types of transport can cause irreparable harm. Designers, directors, creators of multimedia content should also think about how to prevent motion sickness and other discomfort for viewers.

The Work of Richard Russell: The Illusion Of Sexual Differences

In the illustration you can see a man and a woman. But it is not. In 2009, Richard Russell, a psychology professor at Gettysburg College (USA), showed that both individuals are actually versions of the same androgynous face.

The original image is created on a computer by mixing averaged male and female faces. The only difference is in the contrast: in the photo on the left, the contrast and illumination of the facial features are increased, on the right - reduced.

A face with greater contrast is perceived as feminine. It is not precisely known why it was so necessary from the point of view of evolution, but a woman’s face has a greater contrast of light in the region of the eyes, lips, and the surrounding skin than men’s.

Russell’s original research is entitled “A matter of difference in facial pigmentation and exaggeration by cosmetics”. Contrast is an important signal for the perception of sex - the more contrasting the appearance of nature is, the more beautiful the woman seems, therefore cosmetics creating contrast make the woman more attractive.

Kofer's Illusion: Long Lags

In the picture above, most people initially see only squares and only after a few seconds they begin to distinguish 16 ovals of circles.

Anthony Norcia from the Smith-Kettulevel Eye Research Institute (San Francisco, USA) in 2006 demonstrated the illusion of “coffer” - an architectural term meaning a number of recessed square door panels, rectangular or other shapes.

Kofer's illusion belongs to a large class of optical distortions in which a two-dimensional figure or three-dimensional object can be seen in several clearly distinguishable ways. In neurobiology, there is evidence of the emergence of an illusion for some ambiguous figures - due to the fact that our brain is focused on the constant identification of objects.

We do not see the objects as a whole, but in the form of separate faces, contours and figures, which, after a short processing, are grouped into something understandable for our consciousness. However, if the image is inherently ambiguous, the same set of equivalent elements can be interpreted differently - for example, to form a circle or a rectangle.



The illusion of “The Mask of Love”, taken from Gianni Sarkone’s book “Amazing Optical Illusions”, works similarly, with the only difference that the image of one person or two kissing faces does not have one dominant role - what you see depends only on the individual characteristics your brain.



Interestingly, in this way, the brain not only processes information about objects, but also recognizes people's faces. The brain reads a collection of individual elements - the eyes, nose, mouth and ears. In addition to the individual characteristics of facial features, their relationship with each other and location are taken into account. That is, the person is perceived as a whole system. As a result, the Thatcher illusion arises when it is difficult to detect local changes in an inverted portrait photo.



At first, the inverted photo of Margaret Thatcher seems normal, but if you turn it back on 180 ^o again, the wrong position of the eyes and mouth immediately catches the eye. In an inverted photograph, it is more difficult for the brain to assess the image of a whole - information is “collected” separately for each element.

As soon as we are shown the correct face, the perception of a single system suddenly reconnects. The area of ​​the cerebral cortex recognizes the face and determines the direction of the gaze, the amygdala and the insular lobe analyze facial expressions, and the area in the prefrontal area of ​​the frontal lobe and the brain system responsible for the sense of pleasure evaluate its beauty.

Optical illusions in art

Optical illusions are known to people for hundreds of years and, of course, served as a source of inspiration for artists. In the visual arts there is an artistic device associated with optical displacement, which demonstrates an object of easily recognizable form only from a certain point of view. It received the name anamorphosis - from the Greek ἀνᾰ- (prefix with the value of repetition) and μορφή (“image, form”).

The famous painting “Ambassadors” by Hans Holbein the Younger, written in 1533, hides an opaque symbol of the eternal presence of death in everyday life, which only “see the light” reality in a deep understanding of being can see. The easiest way to demonstrate Holbein's mastery in creating anamorphosis is through video.


Intentional distortion of the image creates a special effect. This technique was used by Maurits Escher. Thus, in his work “Belvedere” he created a two-dimensional image of the building for viewing the environs, free from the shackles of the three-dimensional world.



For the viewer, the columns on the second floor have the same size both in front and behind, but the columns in the back are set higher. The viewer will also notice that the upper floor is located at a different angle than the rest of the building. The pillars on the middle floor stand at right angles, but the front struts support the rear side of the upper floor, while the rear struts support the front side.

Impact of neuroprocesses

At the foot of Escher's Belvedere, a person examines the Necker cube - this is another optical illusion, which is also called an impossible cube due to edges that intersect in an impossible way. There is a hypothesis that the neurophysiological channels in the human visual system selectively process information about the depth. These channels operate on the principle of mutual addition - every 2-3 seconds one is activated and the second is suppressed, or vice versa.

This hypothesis may also explain the phenomenon of a more frequent change of variants with prolonged observation. It is assumed that in this case, the recovery processes do not have time to go completely and the change of one option to another is faster. As examples of multistable images in depth, the illusion of a “tiled wall” is called, in which rows of tiles appear to be curved, although they are not at all curved, Schroeder’s stairs, etc.

Hypotheses explaining the existence of various types of illusions are in fact a great many. We all need them to fully understand the processes of identifying ourselves and objects in reality. On the other hand, it is just interesting to observe the illusions, when even the usual perspective in the pictures is the most real illusion of perception.

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The popularity of cognitive and optical distortions reached such heights that the Neural Correlate Society, with the support of the Mind Science Foundation, began to regularly conduct the Best Visual Illusions of the Year competition, where the number of interesting illusions is literally dazzled. Recommended to everyone.