The optical illusions Are visual perceptions that do not fit the reality of the world in which we live S but belong to perception.
In this way, they tell us a lot about how we see and reconstruct everything that surrounds us in our perspective. In fact, all we see is a reconstruction that the mind makes of the reality that surrounds us.
Optical illusion. Although it looks like a GIF image, it is a normal image, JPG format.
The brain, taking into account its innate knowledge of reality, compares that knowledge with all that it observes and draws its own perception and conclusions.
Thanks to the effect of optical illusions, we realize that what our eyes see is not objective, but in the process of seeing it comes into play brain . Thus, the brain interprets and re-elaborates the information that our senses provide us (smell, sight, hearing, smell, and touch).
In the case of optical illusions, the sense involved is the view and can cause distortion in relation to form, dimension, color and perspective.
The use of perceptive deception is something that has always been used at an evolutionary and survival level. We have only to think of the multitude of insects and even predators that camouflage taking advantage of that they have the same color that something of their natural surroundings.
Also, the human being uses perceptual deception for survival. Military uniforms are designed so that the weapons, which also have the same color, go unnoticed in the distance.
25 incredible optical illusions
Next, I will explain, including images, the most amazing optical illusions. If you want to share them, hover over the images and choose your favorite social network.
Crescent Bat
Image created by G. Sarcone
It's not a video or a GIF, I assure you. It is an optical illusion in which a static image appears to be moving due to cognitive effects produced by the interactive color contrasts and the position of the bat shape.
Try to fix your gaze on the bat for 10 seconds without blinking and you will literally hallucinate.
Fading image
He stares at the image for at least 10 seconds without moving his eyes and watches as it disappears slowly. This is a variation of the effect of Troxler which essentially says that if you fix your eyes at a certain point, the stimuli close to that point will gradually fade away.
Monster Illusion
This illusion can be found in many books of Psychology. Although it looks like one bigger than another, the two monstruoson are in fact the same size. Your brain automatically adjusts the images you perceive as distant to compensate for the fact that they are larger than they appear.
If you do not think they are the same size look for a meter and midelas.
Panda
In an attempt to help raise awareness about the plight of the panda, Russian artist Ilja Klemencov created this optical illusion, which contains a panda hidden behind zigzag black and white lines.
If you can not see it try: move up to one meter from the screen, move the head to the left, right or both sides.
If you detect the panda you will notice that it is the famous World Wildlife Fund (WWF) logo.
Where are the animals of the forest?
Green Blue
There are several variations to this optical illusion, but the effect is the same. The"blue"and"green"backgrounds are in fact the same color.
You do not believe me? Seal the two images in photoshop or with paint and you will see it.
Cat climbing stairs... or are they coming down?
The image of the old / young
We begin the article with one of the best known illusions. Surely you know her too. It is an image in which you can see indistinctly depending on the moment and the perception of a young woman or an old woman. You always see one of the two before the other.
Dancer
Created by the web designer Nobuyuki Kayahara, some people have the figure turning clockwise, while others see it turning counterclockwise.
What do you think? Leave your opinion in the comments!
Pac-man Illusion
If you stare at the center cross for at least 15 seconds you will start to see several green lights around the circle of magenta disks. After a few more seconds, the magenta discs will begin to disappear until everything you see is a green disc that goes in a circle around the cross.
The Illusion of Zöllner
This illusion was discovered by the German astrophysicist Johann Karl Friedrich Zöllner In 1860, hence its name. In the image, different small lines are seen. Although they seem to bow, this is an optical illusion due to diagonal lines. Actually the small lines are straight.
Motion Illusions
These images are static, even if there seems to be movement. To check it, cover a part of the image and you will see there is no movement.
Circles that move...
They do not move, even if for your brain. Colors and shadows are responsible for the sensation you have when you look at this image of the circles moving. This illusion affects peripheral vision.
If you notice, if you stare at one of the circles, the circles will surprise us by moving. This image is based on the work of the psychologist Akiyoshi Kitaoka.
The Illusion of Shadow
Probably one of the most incredible illusions there is, it was published by Edward Adelson, a professor at MIT. Although the square"A"appears to be darker than the square"B", they are of the same color.
The sparkling grid or bright grid
This illusion was discovered by the author E. Lingelbach in 1994. In it, if we do not look at a specific point and focus on the image in general, we perceive blackheads and whiteheads alternating at intersections.
On the other hand, if we look at a fixed intersection (we can do this with several intersections), we will see that there is no black spot. Again, this is a product of our perception.
Cornsweet Effect
In this effect, the visual system takes the dark gray and white of the edges and extends it through the squares.
In the image, if you put the finger in the middle of the two cubes you will see that both cubes are observed of the same color. On the other hand, if you remove the finger again you will see the top one darker than the one below.
How big are the cars?
In the image above it seems that the cars are of different size but... Look at the following image:
Jastrow Illusion
The discoverer of this illusion was the American psychologist Joseph Jastrow In 1889. In the image below, it seems to be observed that figure A is smaller than figure B. It is not so, both are equal.
As this illusion is difficult to see that what I am commenting is real, then I leave you a video where it is explained very well how both figures are the same size.
The Ames Room
This illusion owes its name to the American psychologist Adelbert Ames, who created this room.
It has the peculiarity that, although it seems normal if it is seen from the front and in the center, it is actually trapezoidal. That is, both the walls and the floor and ceiling are sloped. Next I show you a map of how the room is constituted.
So that you can see it in a very visual way, I leave you this video in which the effect of the illusion is perceived:
This illusion has been used in the cinema, in the well-known film"The Lord of the Rings".
Illusion of the square
The square of the image appears to be irregular. Instead, it is completely regular. This is because the way in which the black pictures are arranged makes us see it distorted.
Where do you look at the chair?
Illusion of rotating circles
In order to be able to perceive this optical illusion, we must fix our eyes on the center point for a few seconds. Then we'll head back and forth. Can you see how the circles move?
Illusion of circle size
The author of this illusion is Ebbinghausen. In this image, both circles are really the same size even though we see them differently (we see the one on the left larger than the one on the right).
This is due to the circles around you. Because the adjacent circles on the left are smaller, relative to these, the larger middle circle is seen. The effect is the opposite in the image on the right. As the circles around are larger, the center circle is perceived to be smaller.
How many legs does the elephant have?
It only has 4 legs!
Illusion of Müller-Lyer
Looking at the image, the center line of the image on the right seems longer. However, this is due to the placement of the horizontal lines of the ends. TO
Being in an outward orientation, in the image of the right is perceived of greater length the straight of the center. That is, an elongation or shortening effect of the length of the segment occurs.
13- Optical illusion of the central point
This illusion is perceived if we keep our gaze at the central point of the image below. When we do this, the dark center of the image expands. There really is no such expansion. It is, once again, a product of perception.
14- Rubin Vase
This is another of the most famous optical illusions since it has been used in the Psychology of the Gestalt . It is within the cognitive illusions of ambiguity
. It was developed by the Danish psychologist Edgar Rubin in 1915 in his work Synsoplevede Figurer (in Spanish, Visual figures). This image represents a double vision, on the one side of a vase and on the other side of two faces facing each other.
Two women or...
Double image illusion
In this other image, you can see both a saxophonist and the face of a girl, although one is usually perceived more quickly than the other depending on the person. Can you see both?
An optical illusion that we find in the day to day is the one that is used in the cinema. In this art certain effects are used related to the animation, considered this as an optical illusion since it perceives a movement in something really static.
They are also and have been widely used in quantity of works of art with the aim of provoking in the viewer a false impression of form, dimension, depth or perspective.
The mental alteration that a person can suffer at a certain time, or even permanent, can also cause involuntary optical illusions to appear.
Studies have shown that the longer the observation time, the greater the distortion experienced.
Circle white-black-Koffka ring
The first semicircle on the left seems to be white, while the semicircle on the right looks black... However they are the same.
You do not believe me? Seal the semicircles with your hand and you will see.
Blivet 2-3
This is one of the most famous optical illusions of an object. Has 2 tips Rectangular at one end that are transformed into 3 teeth Cylindrical in the other.
Street painting
Pareidolia
Do you see anything else apart from the mountain?
A Pareidolia Is an illusion created by the brain to see faces in nature or in other places, such as houses, bags or any type of object.
Light bulb
Stay watching the bulb for 25 seconds. Then look at a white sheet or white wall. Do you see?
You should see one see a bright bulb.
In conclusion, we can say that the brain receives so much information that it tends to jump to conclusions quickly according to what it already knows and that, beyond what we could imagine, we do not observe of objective form the world that surrounds us.
Squares that seem to move
Akiyoshi Kitaoka
Causes of optical illusions
In addition to being the cause of the brain, there are other causes for optical illusions. Next, I will go on to detail the various causes:
Physiological
We can speak of the physiological causes of an optical illusion when it is caused by a glare due to an intense luminous stimulus that leaves the light receptors of the retina saturated for a few seconds. This is due to errors in the connections between the brain hemispheres .
An example of optical illusions by physiological causes are post-images. The post-images are the images that are apparently printed in our view after observing a very luminous object. In general, they result in an excess of visual stimulation, whether this movement, brightness, color, etc.
The explanation for why this occurs is found in that the stimuli have individual neuronal paths for the early stages of visual processing, and a repeated stimulation of only some of those paths confuses the visual mechanism.
Cognitive
They are based on the vulnerability of the visual system. Thus, a figure will seem to be a thing that is not really.
Cognitive illusions are divided into: fictional illusions (or hallucinations), paradoxical illusions, illusions of distortion, and, finally, illusions of ambiguity.
The perception of the optical illusions varies from one person to another, and in this variance are involved several factors such as visual acuity, visual field or perimetry, astigmatism or Colour blindness .
Some investigations
The research of the author Gregory (1969) showed that considering that the correspondence of properties visually perceived and objective is called constancy, and, on the contrary, the non-correspondence is called illusion, there is a pole Constancy-illusion.
Between these two extremes, an infinite number of perceptual outputs can be given. The result of the perception will depend on the information acquired through the stimulating medium, having special importance the keys of depth and perspective.
This author classifies illusions into 3 types:
- Impossible objects : They are figures that can not be perceived as a single object only.
- Distorted figures : They are figures that appear longer, or shorter, or unduly curved.
- Figurative posts : It is the illusion that occurs in a determined figure as a result of having perceived, immediately before, another figure different.
Although there is no unified theory of all illusions, authors David Hubel and Torsten Wiesel discovered through research that there are certain neurons located in the Visual cortex Of the brain that activate only when we observe objects oriented towards certain angles.
More recently, a study examining Necker's Cube , It was observed that in people observing this cube the brain could vary between two different interpretations of the same image, while trying to convert a two-dimensional image into a three-dimensional image.
Classification of optical illusions
- Figurative Illusions : They are distortions of position, size, length or alterations of form. These occur in linear representations and are produced because of ocular fixation on a previous form. That is, they are phenomena of contrast between successive figures. An example of this kind of optical illusion is the illusion of Müller-Lyer.
- Illusions in three dimensions : They often occur when two sets of visual information are combined at the same time. An example of this illusion is the distorted Ames room.
- Linear illusions : Are those that are produced directly because of the special arrangement of the lines. An example of this is Zollner's illusion.
References
- Franz V. H., and Scharnowski F. Gegenfurtner. 2005."Illusion effects on grasping are temporally constant not dynamic."J Exp Psychol Hum Percept Perform. 31 (6), 1359-78.
- Franz V. H., and Scharnowski F. Gegenfurtner. 2005."Illusion effects on grasping are temporally constant not dynamic."J Exp Psychol Hum Percept Perform. 31 (6), 1359-78.