Illusions often lead to completely incorrect quantitative estimates of real geometric quantities. It turns out that you can make a mistake of 25% or more if your eye estimates are not checked with a ruler.
Visual estimates of geometric real quantities very much depend on the nature of the image background. This applies to lengths (Ponzo illusion), areas, radii of curvature. It can also be shown that what has been said is also true for angles, shapes, and so on.
Ponzo illusion is an optical illusion first demonstrated by Italian psychologist Mario Ponzo (1882-1960) in 1913. He suggested that the human brain determines the size of an object by its background. Ponzo drew two identical segments against the background of two converging lines, like a railway track stretching into the distance. The top segment appears larger because the brain interprets converging lines as perspective (like two parallel lines converging in the distance). Therefore, we think that the upper segment is further away, and we believe that its size is larger. In addition to converging lines, the strength of the effect is added by the decreasing distance between intermediate horizontal segments.
Some researchers [ Who?] the moon illusion is believed to be an example of the Ponzo illusion, in which trees, houses, and other landscape features act as converging lines. Foreground objects trick our brains into thinking the Moon is larger than it actually is.
This type of visual illusion also occurs when using a sensory substitution device. However, its perception requires the presence of such visual experience, since people with congenital blindness are not sensitive to it.
Shapeshifting is a type of optical illusion in which the nature of the perceived object depends on the direction of gaze. One of these illusions is the “duck hare”: the image can be interpreted as both an image of a duck and an image of a hare.
1. Introduction
2. General characteristics of perception
3. General characteristics of visual illusions
4. Illusions of size perception
5. Distortion Illusions
6. Illusions arising from changing terrain and depending on perspective
7. Illusions arising from the background on which the figure
8. Portrait illusions
9. Illusions when an object moves
10. Illusions and the influence of knowledge about an object on perception
11. Illusions and the influence of previous experience on perception
12. Other types of illusions
13. Bibliography
Introduction:
The theme of my work is illusions of perception. According to the definition of the Psychological Dictionary, illusions of perception (from the Latin illusere - to deceive) of particular characteristics of certain objects.
The most numerous group of perceptual illusions are spatial visual illusions.
There is no consensus on the classification of illusions in the psychological literature.
In my work, I classified illusions as follows:
1. Visual illusions:
a) illusions of size perception;
b) illusion distortion
c) illusions arising from changing terrain and depending on perspective
d) illusions arising from the background on which the figure is located
e) portrait illusions
f) illusions when an object moves
g) illusions of color perception
2. Other illusions:
a) auditory illusions;
c) other illusions
General characteristics of perception:
Perception - a very complex, but at the same time, a unified process aimed at understanding what is currently affecting us. This is a reflection of objects and phenomena in the totality of their properties and parts. It includes a person's past experiences in the form of ideas and knowledge. Whatever a person perceives, everything invariably appears before him in the form of holistic images.
Let's say we are watching a child playing. It occupies a certain place in space, is located at a certain distance from us and in a certain direction; we see it sometimes moving, sometimes motionless, we know that we can touch it, unlike, for example, the sky. He wears clothes of certain colors. If he collides with a small object, we get the impression that the child is the cause of his movement. All this is perceived by us through vision. But we also hear his laughter, and this sound has a certain pitch, volume and timbre and comes from a certain part of space. We perceive it in the totality of its properties, and from our past experience we know that in front of us is a child.
The process of perception occurs in connection with other psychological processes of the individual: thinking (we are aware of what is in front of us), speech (we can realize that in front of us only when we can call the perceived image: a child), feelings (we relate to what we perceive), will (in one form or another we arbitrarily organize the process of perception).
Perception may not be entirely adequate; for various reasons, the object may be perceived distorted or ambiguous.
General characteristics of visual illusions:
Distortions of the visual image are otherwise called visual illusions. This is an incorrect or distorted perception of the size, shape and distance of objects. The nature of illusions is determined not only by subjective reasons, such as attitude, direction, emotional attitude, etc., but also by physical factors and phenomena: illumination, position in space, etc.
The fact that the vast majority of people sometimes receive the same erroneous visual impressions indicates the sufficient objectivity of our vision. The vast majority of visual illusions arise not because of the optical imperfection of the eye, but because of a false judgment about what is visible, so we can assume that deception here arises when comprehending the visual image. Such illusions disappear when certain factors that interfere with correct perception are eliminated.
Sometimes visual illusions appear due to special observation conditions, for example: observation with one eye, observation with fixed axes of the eyes, observation through a slit, etc. Such illusions disappear when unusual observation conditions are eliminated.
Finally, a number of illusions are known that are caused by the optical imperfection of the eye and some special properties of various analyzers involved in the visual process (retina, nerve reflexes).
Close your left eye and look at the figure depicted on the left with your right eye, holding the drawing at a distance of 15-20 cm. At a certain position of the drawing relative to the eye, the image of the right figure ceases to be visible.
In 1668, the famous French physicist E. Mariotte discovered the “blind spot” phenomenon. At the point where the optic nerve enters the eye, the retina of the eye does not have light-sensitive nerve fiber endings. Therefore, images of objects falling on this place of the retina are not transmitted to the brain and, therefore, are not perceived. A blind spot, it would seem, should prevent us from seeing the entire object, but under normal conditions we do not notice this. Firstly, because the images of objects falling on the blind spot in one eye are not projected onto the blind spot in the other; secondly, because the falling parts of an object are involuntarily replaced by images of neighboring parts or the background surrounding this object.
Illusions of size perception:
In the picture, the white square on black appears larger than the black square on white. In fact, the figures are the same. This illusion is explained by the phenomenon irradiation (in Latin - irregular radiation): light objects against a dark background seem larger than their actual size and seem to capture part of the dark background. This occurs due to imperfection of the lens. Knowing this property of the black color to conceal size, duelists in the 19th century preferred to shoot in black suits in the hope that the enemy would miss when shooting.
We perceive objects holistically, together with other objects, background or environment surrounding them. And this explains the largest number of visual illusions encountered in practice.
Often illusions are explained by the fact that we mistakenly transfer the properties of a figure to its parts.
The segments in the figure are equal, although the top one seems larger (Müller-Lyer illusion).
Another example of an illusion of this kind: Sander's parallelogram (1926).
In fact, the segments AB and BC are equal.
Visual illusions can arise due to the so-called general psychological law of contrast, i.e. due to the relationship of figures with other figures.
In the figure, the circle adjacent to the sides of the acute angle appears larger than the other, while their sizes are the same.
In the picture, the inner circle on the left appears larger than the inner circle on the right.
Another example of a contextual illusion: the man next to the giant appears smaller than the figure in the background, even though it is the same figure placed in the drawing without changing size.
The reason for some illusions of size perception lies in the insufficient ability of the visual apparatus to isolate a part from the whole - due to the complexity of the situation. For example, in a chaos of lines of the same color, brightness and thickness, it is not immediately possible to identify (recognize) a specific figure.
A special type of size illusion is the overestimation of vertical lines compared to horizontal ones, which is typical for most people.
If you ask a number of people to draw vertical and horizontal lines of the same length, then in most cases the drawn vertical lines will be shorter than the horizontal ones.
Here are two examples of vertical line overestimation illusions:
A vertical line is perceived as longer.
If you look at the drawing with one eye, the effect is somewhat reduced.
Look at the numbers "3" and "8". It seems to you that the top half of each number is equal to the bottom.
Let's turn these numbers around.
The difference in size between the top and bottom halves becomes apparent. In addition, vertical parallel lines, when they are significant in length, usually appear slightly diverging at the top, and horizontal ones - converging.
The group of illusions under consideration also includes illusions of filled space. The filled space through which the eye slides horizontally lengthens. So, for example, at sea all distances seem smaller, since the boundless expanse of the sea is an undivided space. Buildings decorated with figures and ornaments seem to us larger than their actual size.
Even in ancient times, people were confused by the fact that the moon and sun appeared larger on the horizon than when they were high in the sky. This optical illusion is called moon illusion . The effect is that the presence of the earth gives the impression that the moon at the horizon is further away than the moon at the zenith, since the filled space between the observer and the horizon gives the impression of greater extent than the unoccupied space between the observer and the sky above. Therefore, it seems to us that the moon on the horizon looks larger than the rising moon.
Shape perception
Any object has a certain appearance, called form. The form personifies the qualitative originality of the totality of geometric parameters of objects (flat and three-dimensional). The perception of a planar form consists of distinguishing the outlines of an object, its contour. In this case, the boundary is not just highlighted, but the gaze (or the hand when touching) moves along this boundary, and in the most informative places makes numerous return movements.
The perception of three-dimensional form includes the perception of distance and volume. The role of deep sensations explains a number of dependencies between the perceived shape, distance and size of objects. Thus, the perception of close objects is saturated with deep sensations, so they seem smaller compared to exactly the same ones, but located a little further away. As one moves away from the viewer, three-dimensional objects seem more and more flat as deep sensations weaken. Thus, a cube up close appears elongated in the direction away from the observer, and at a distance it appears flattened.
In principle, the shape of objects can be perceived, in addition to vision, touch and kinesthesia (primarily through hand movements in general), and with the help of hearing, which is proven by the abilities of bats, dolphins and other animals that use echolocation for orientation in space. But man does not have such abilities. 1
Perception of size (magnitude)
The size of objects with the help of vision is determined, firstly, by the size of their images on the retina and, secondly, by an assessment of their distance from the observer. Clear vision of objects at different distances, and, accordingly, determination of their true size is carried out using two physiological mechanisms: accommodation and associated convergence.
Accommodation is a change in the breaking ability of the eye lens by changing its curvature. When viewing close objects, the lens lens becomes more convex, while distant objects become flatter. With age, the elasticity and mobility of the lens decreases, resulting in farsightedness.
Convergence is the bringing together of the visual axes on a fixed object. Associated with accommodation.
A combination of two factors - the size of the image on the retina and the tension of the eye muscles as a signal of the size of the perceived object.
Visual perception of size often leads to errors in assessing the true size of objects. One of the most common mistakes is overestimating vertical dimensions. This occurs because vertical eye movements are accompanied by reflex divergence, which requires compensatory efforts of reverse convergence to keep the gaze on the object. Additional muscle efforts are “read” by the brain (and psyche) as additional size or bringing the object closer to the observer.
The well-known “moon illusion” is associated with the same effect: at the horizon the moon appears larger than at the zenith. Since the time of Ptolemy, it has been believed that this phenomenon has something to do with the apparent distance. The most thorough study of this phenomenon was undertaken by E. Boring. Now this fact is explained by the appearance, when viewing the moon at its zenith, of those additional efforts of the eye muscles necessary to maintain the initial convergence. This, in turn, is a sign of a decrease in the distance to the object. If the moon now appears closer at the zenith than at the horizon, then its size appears smaller, since the size of the retinal image has not changed. 1
Another type of error in visual perception of magnitude is associated with our social attitudes. The general tendency is this: socially significant objects appear to us to be larger in size than those of equal size, but less significant.
Diagram of oxygen transfer by hemoglobin. Hb - hemoglobin hb+o2 hbo2 hbo2 hb+o2 hbco2 hb + CO2 hb + CO2 hbco2. Think! Biology lesson, 8th grade. But millions of ships leave their harbors to sail again.” Hemoglobin molecule. Objective of the lesson: Plasma; Serum; Thrombus; Fibrin; Fibrinogen; Phagocytosis; Blood clotting; Phagocytosis is the process of absorption and digestion of microbes and other foreign substances by leukocytes. Lesson topic:
"Primroses"- Why do primroses bloom so early in the spring? Purpose of the study. The flowering period of oak anemone occurs in the 1st – 12th year of life in April – May. A special sign of early spring is the early spring flowering of snowdrops. The flower is solitary, the perianth is white, with 6 reddish leaflets on the outside. Conclusion: on average, in the vicinity of the village of Arkhipyata, the oak anemone blooms on April 20.
"The body's digestive system"- The process of digestion mainly occurs in the small intestine. It is a derivative of the hindgut. Conventionally, there are three sections of the digestive system. Composition of the digestive system. The anterior section includes the organs of the oral cavity, pharynx and esophagus. Functions of the digestive system. Anterior section of the digestive system. Fats. Organs of the digestive system. Digestion and the digestive system. Digestion.
"Biology 8th grade Digestion"- Gastric juice. Industrial premises. reflex arc BAS food mucous membrane. Action of gastric juice. Control system. Internal structure of the stomach. Manufacturing process. Qualified personnel. Human. 8th grade". Production equipment. 37-39o, hcl. FOOD digestion NUTRIENT SUBSTANCES. Unconditioned reflexes blood Conditioned. M.: Bustard, 2005), fill out the table.
"Fish Organs"- Questions for repetition. How does food pass and change in the body of a fish? Circulatory organs. Explain why a fish that is taken out of the water dies. Digestive organs of fish. Nutrition, breathing, blood circulation of fish. What chambers does the two-chambered heart of fish consist of? Biology, 8th grade. How and what do fish eat? Respiratory system.
"The importance of vitamins"- The importance of vitamin C Participate in redox processes. Participate in hematopoiesis. The importance of B vitamins Participate in the work of oxidative enzymes. Main content What are vitamins? Protects cell membranes and other important cell organelles from unnecessary oxidation. Participate in the most important processes of synthesis and breakdown of substances. What vitamins exist? Vitamins. Purpose of the work: to find out why vitamins are needed. Participate in amino acid metabolism.