Préparez-vous à avoir le cerveau retourné par des illusions d'optique qui vous feront perdre la tête ! L'une des plus spectaculaires est l'effet Thatcher, ou illusion de Thatcher — c'est lorsque qu'un visage à l'envers semble normal, mais retournez-le à l'endroit, et soudainement, les traits deviennent hilarieusement déformés. Cela se produit parce que notre cerveau traite les visages différemment lorsqu'ils sont inversés, ce qui fait que nous manquons la bizarrerie. Mais ce n'est que le début — d'autres illusions, comme la pièce d'Ames, jouent avec votre sens des tailles et des perspectives, rendant une personne géante et une autre minuscule. Ensuite, il y a l'illusion du mur de café, où des lignes droites apparaissent inclinées en raison de motifs contrastants. Chacune de ces illusions prouve que vos yeux peuvent jouer des tours vraiment rusés à votre cerveau. Animation créée par Sympa.
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Musique par Epidemic Sound https://www.epidemicsound.com
Pour ne rien perdre de Sympa, abonnez-vous!: https://goo.gl/6E4Xna
----------------------------------------------------------------------------------------
Nos réseaux sociaux :
Facebook: https://www.facebook.com/sympasympacom/
Instagram: https://www.instagram.com/sympa.officiel/
Stock de fichiers (photos, vidéos et autres):
https://www.depositphotos.com
https://www.shutterstock.com
https://www.eastnews.ru
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Si tu en veux encore plus, fais un tour ici:
http://sympa-sympa.com
Category
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FunTranscript
00:00Don't you think Harry Styles looks a bit strange?
00:04Of course, he's upside down.
00:06But that's not what we're talking about.
00:08There's something even stranger here.
00:10And I'll give you a second to try to guess.
00:13Look closely at every detail of this photo.
00:16So, have you noticed it?
00:18Look at his mouth and his eyes.
00:20Although everything else is inverted,
00:22these two elements seem normal.
00:24In other words, they are correctly oriented.
00:27However, I bet you only noticed it after I told you, didn't you?
00:32This phenomenon is called the Thatcher effect.
00:35Our brains are designed to recognize faces in their natural position
00:39by analyzing them globally and identifying the details in an instant.
00:43But when a face is turned over,
00:45it becomes much more difficult to detect anomalies.
00:48So, at first glance,
00:50you might think that the mouth and eyes are also upside down,
00:53just like the rest of the face.
00:55Be careful.
00:56This is not a simple monotonous image of black and white stripes.
01:00I assure you that there is something,
01:02or rather someone, hidden behind these lines.
01:05To solve this mystery,
01:07you just have to shake your head quickly.
01:09If it seems uncomfortable or inappropriate to you,
01:12especially in the presence of your colleagues,
01:14there is an alternative.
01:16If you use a laptop,
01:18tilt the screen slightly,
01:20back and observe the image from an oblique angle.
01:23Do you see Taylor Swift appearing?
01:25Yes, here she is.
01:27Masks have something disturbing
01:29that always makes me uncomfortable.
01:31And here, things are going to get even more disturbing.
01:34For now, it's just a mask turning very slowly.
01:38Well, go on.
01:39Oh, wait.
01:40Do we see the front of the mask again?
01:42This is not really the case.
01:44The mask is still rotating.
01:46This phenomenon is called the illusion of the hollow face,
01:49or illusion of the hollow mask.
01:51What happens is that our brain
01:53lets itself be fooled by perceiving the back of the mask,
01:56the concave part,
01:58as if it were the front,
01:59that is, the convex part.
02:01In other words, instead of seeing the back as hollow,
02:04most of us imagine it as a normal face
02:06coming out towards us.
02:08This illusion works because our brain
02:10relies on what it expects to see,
02:12a relief face,
02:14rather than on what is really there.
02:16In a way, it refuses reality by saying,
02:18No, I'm sure it's a classic face.
02:21Here is another fascinating illusion
02:23based on rotation.
02:25Give us your opinion in the comments.
02:27Do you see a young woman turning to the right or to the left?
02:30This illusion,
02:32called the rotating dancer,
02:34or the illusion silhouette,
02:36has intrigued netizens since 2003.
02:39Some say they see the rotation
02:41in the direction of the needles of a watch,
02:43while others are convinced
02:45that it is done in the opposite direction.
02:47So, who is right?
02:49The short answer? Both.
02:51The detailed answer?
02:53It is an optical illusion
02:55that plays with our perception of depth.
02:57At certain moments of rotation,
02:59it becomes difficult to determine
03:01if the dancer's arms move
03:03in front or behind her body.
03:05In response, our brain guesses,
03:07creating the illusion that it can turn
03:09in one direction or the other.
03:11What makes this illusion even more interesting
03:13is that by adding a few landmarks,
03:15the dancer stops moving.
03:17He then becomes able to discern
03:19the direction of the rotation,
03:21although the initial illusion
03:23works in both directions.
03:25Can you spot an anomaly on these photos?
03:27Strangely, you may not have noticed
03:29that the upper half of the two clichés
03:31represented exactly the same image
03:33of Ryan Gosling.
03:35But why do we feel
03:37that these are two different photos?
03:39This phenomenon is known as
03:41composite face illusion.
03:43With the lower half of another,
03:45our brain interprets it
03:47as a whole new face.
03:49Each half disturbs the perception of the other,
03:51making them indissociable.
03:53However, this illusion works mainly
03:55when the face is in its normal position.
03:57If we turn it or unalign
03:59the two parts,
04:01our brain manages to better dissociate them,
04:03which allows us to recognize
04:05the original faces more easily.
04:07This then reveals that the two upper parts
04:09are perfectly identical.
04:11Why do we see Adele's head floating
04:13alone in the middle of nowhere?
04:15Let's add a background to give a little context.
04:17Oh, wow!
04:19This is not exactly what I expected.
04:21But let's go.
04:23Now, look around Adele.
04:25Do you think the background is moving or not?
04:27Do you have the answer?
04:29In reality, the background gives the impression of moving,
04:31but it is totally still and flat.
04:33If you have any doubts,
04:35pause the video.
04:37You will see that the purple and yellow waves
04:39seem to continue to move
04:41in a frenetic way.
04:43This phenomenon is due to a pattern
04:45specially designed to deceive your brain,
04:47using contrasting colors,
04:49shapes and positions
04:51that create this illusion of movement.
04:53Our brain interprets
04:55the variations of light as a movement.
04:57Hence this impression that the lines move.
05:01But there is even more fascinating.
05:03Fix your eyes only on Adele
05:05and try not to blink.
05:07Stay focused on her.
05:09So, did you notice that the illusionary movement
05:11seemed to slow down?
05:13Amazing, isn't it?
05:15Many optical illusions
05:17found on the internet rely on the effect of contrast.
05:19They play on the way
05:21our brain interprets things
05:23according to comparisons.
05:25Our perceptions can be amplified or reduced
05:27depending on what they are confronted with.
05:29Do you want an example?
05:31Let's take a picture of Dua Lipa.
05:33Let's duplicate it and apply a gray filter.
05:35The two images
05:37are exactly the same color and shade.
05:39However,
05:41when we add a light gray background to one
05:43and a black background to the other,
05:45our perception changes.
05:47The gray tones of Dua Lipa's pictures
05:49seem different, don't they?
05:51If you don't perceive the effect with this image,
05:53don't panic.
05:55Here is a simpler demonstration.
05:57Look at these two gray rectangles in the center.
05:59They are strictly the same color.
06:01However, you probably see
06:03the one at the bottom as darker.
06:05Why?
06:07Because it is surrounded by a lighter shade,
06:09unlike the one at the top.
06:11Everything depends on the way
06:13our brain interprets the elements
06:15by taking into account their environment.
06:17Ready for the adventure?
06:19Look at this ruler
06:21while we prepare to put the sails on.
06:23So, in which direction does it turn?
06:25Right or left?
06:27Well, it depends,
06:29because you have the possibility to control it.
06:31Now, tilt your head to the left
06:33and you will see the ruler turn in one direction.
06:35Now, tilt it gently to the right,
06:37without rushing.
06:39Do you notice what happens?
06:41It looks like the ship is changing course.
06:43A similar phenomenon occurs here.
06:45This time, the image of the circle
06:47remains completely still,
06:49but you can give it the appearance of movement.
06:51Focus on the black dot in the center
06:53and swing your head back and forth.
06:55You probably see the circle turn.
06:57This illusion is explained by the way
06:59our brain decodes the direction of the movements
07:01based on the ends of the lines
07:03and their angles.
07:05These contradictory signals
07:07create an impression of rotation.
07:09You probably have the impression
07:11that this image is tilted,
07:13as if the columns, especially those in the center,
07:15seemed to be curving.
07:17But once again, your brain plays tricks on you.
07:19Look carefully.
07:21If we add white lines forming a rectangle,
07:23you will notice that the vertical and horizontal lines
07:25are actually perfectly straight.
07:27Let's finish with a little fun exercise.
07:29The next time you pass in front of a retro barber,
07:31stop to observe the usual pole.
07:33Hypnotizing, isn't it?
07:35The red and blue stripes
07:37give the impression of going up
07:39or down endlessly.
07:41But in reality,
07:43they do not move at all in this direction.
07:45They simply turn around the pole,
07:47horizontally.
07:49What creates this illusion
07:51is the diagonal orientation of the stripes.
07:53When the pole turns,
07:55instead of perceiving a simple circular movement,
07:57we have the impression that the stripes
07:59go up or down along the pole.