optical illusions - biovis · • studying optical illusions helps us to understand deeply how our...
TRANSCRIPT
![Page 1: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/1.jpg)
OPTICAL ILLUSIONS Matyas Molnar
![Page 2: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/2.jpg)
• Mohit Gupta: Understanding optical illusions
• https://www.eyebuydirect.com/understanding-perception-optical-illusions
• https://www.rd.com/culture/optical-illusions/
• https://www.thisisinsider.com/classic-optical-illusions-2018-1#this-is-troxlers-fading-circle-if-you-stare-the-dot-for-at-least-20-seconds-the-circle-will-completely-fade-away-20
• https://interestingengineering.com/11-puzzling-optical-illusions-and-how-they-work
• https://www.collective-evolution.com/2017/07/26/ex-nasa-scientists-share-concealed-information-about-the-face-pyramid-found-on-mars/
• https://www.buzzfeed.com/arielknutson/people-who-found-jesus-in-their-food
More info, examples, sources
![Page 3: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/3.jpg)
Preface • Microscopy is a visualization technique
– the danger: we tend to believe what we see but humans are fooled by their vision in many different ways
• We see / don’t see what we
– want / don’t want to see – learnt / didn’t learn to se – others expect / don’t expect us to see
• Humans are not rational beings. Our perception and decisions are governed by our emotions and earlier experiences. We make decisions emotionally, only later we justify them with logical explanations.
• Biggest effects and limitations are in the following levels: – Eyes – Brain – Environment – Culture, religion, belief systems
• We cannot perceive the world objectively outside of our box • Is there any objective world outside us?
![Page 4: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/4.jpg)
Preface
• Many times there are no consensus on how an actual optical illusion works.
• Hard to explain optical illusions with one unified theory, numerous factors are involved
• There are various theories and counter theories, and sometimes it's also not clear if the illusion or type of illusion acts on the physical visual system or on the brain level.
• Studying optical illusions helps us to understand deeply how our vision and brain work
![Page 5: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/5.jpg)
Brightness-contrast illusions
![Page 6: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/6.jpg)
Brightness-contrast illusions • Our visual system (eyes and/or brain) tries to
compensate for differences in illumination
• We are responsive to gradients (changes) rather than absolute values – Such as our body doesn’t sense the temperature, it senses
the change in temperature
• These illusions can happen at eye or brain level
![Page 7: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/7.jpg)
A Brightness Illusion
![Page 8: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/8.jpg)
Simultaneous Contrast Illusion
![Page 9: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/9.jpg)
Craik-O’Brien-Cornsweet Illusion
Actual Profile
Perceived Profile
![Page 10: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/10.jpg)
Lightness Constancy
![Page 11: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/11.jpg)
The Hermann grid illusion
![Page 12: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/12.jpg)
Scintillating Grids: Straight and Curved
Scincillating black dots No black dots
![Page 13: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/13.jpg)
Color illusions
![Page 14: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/14.jpg)
Color illusions – colors in real • Colors don’t exist
• The colors we see are just products of our brain
(emotion)
• In the physical world, periodic oscillations of electromagnetic radiation exist, we can characterize them by amplitude, frequency, wavelength and phase.
• Do I see blue the some way (same color) as you see?
![Page 15: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/15.jpg)
Color illusions - limitations in our sensor • We can sense EM radiation between in
a limited way, 400-700nm • We mainly see at around 550nm (green) • We can only sense three colors: blue,
green and red. To the different ratios of the RGB signals from our eye, our brain associate a sensation (emotion), that’s how we perceive millions of color.
• Afterimage – rods and cones are overstimulated and loses sensitivity (adaptation). Complementary color is burned in for a while.
• Our visual system (eyes and/or brain) tries to compensate for environmental differences (shades, tones, hues)
![Page 16: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/16.jpg)
Which image is higher in intensity?
![Page 17: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/17.jpg)
Rubik’s Cube Color Illusion
Same Color?
![Page 18: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/18.jpg)
Rubik’s Cube Color Illusion
One of the most powerful color illusions. You know you are fooled But you still can’t believe it. Try to flip back and forth.
![Page 19: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/19.jpg)
![Page 20: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/20.jpg)
The two dogs have the same color
![Page 21: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/21.jpg)
Both skulls are red
We see purple and orange skulls. A type of Munker- White brightness illusion in color, the phenomenon causes an image to bias toward the color of the objects that surround it (left: blue lines; right: yellow lines).
![Page 22: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/22.jpg)
A color illusion from our time
What is the color of the dress? White-gold or blue-black?
![Page 23: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/23.jpg)
Afterimage
![Page 24: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/24.jpg)
![Page 25: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/25.jpg)
Bending the lines
![Page 26: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/26.jpg)
Are the lines parallel? Straight?
![Page 27: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/27.jpg)
Café Wall Illusion
![Page 28: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/28.jpg)
A variant of the Café Wall Illusion
![Page 29: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/29.jpg)
![Page 30: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/30.jpg)
The Fraser Spiral Illusion
This one is an extremely strong illusion. Even if you trace it with
your finger, you go down a spiral
![Page 31: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/31.jpg)
Pinna’s Intertwining Illusion
Concentric or intersecting circles?
![Page 32: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/32.jpg)
”Moving” illusions
![Page 33: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/33.jpg)
”Moving” illusions • Small, rapid eye movements are responsible for the illusion. If we
focus on one spot, all movements will stop. – Voluntary or involuntary eye movements (saccades) are mainly erased
from our vision by the brain. When looking into the mirror, try to catch your eye movements. Most possible you can’t “see” them as the brain removes them (saccadic masking), since it was taught to create a steady image and only concentrate on “important”, clear details. Many things that we physically see are removed or re-shaped by our brain. We see with our brain, earlier experiences, expectations, culture, etc…
• Explanation with Moiré effect: similar, repetitive patterns merged
together at slightly different angles, creating interference and a rippling effect
• Another possible explanation is that our visual system cannot bring the blurred boundaries within the image into focus, and our brain cannot adjust.
![Page 34: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/34.jpg)
Spinning Wheel Illusion
![Page 35: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/35.jpg)
Spinning seeds Illusion
![Page 36: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/36.jpg)
Spinning colors
![Page 37: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/37.jpg)
Works also in 3D
![Page 38: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/38.jpg)
Seeing things that it’s not there and the opposite
![Page 39: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/39.jpg)
Where is the lake?
![Page 40: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/40.jpg)
Kanizsa's Triangle
![Page 41: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/41.jpg)
Are you sure?
What does the sign say?
![Page 42: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/42.jpg)
Size and perspective
![Page 43: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/43.jpg)
Size and perspective • The surroundings, environment and
perspective can fool our visual system
• We cannot estimate correctly the size of an object if it’s compared with other objects
![Page 44: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/44.jpg)
Ebbinghaus illusion
![Page 45: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/45.jpg)
![Page 46: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/46.jpg)
![Page 47: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/47.jpg)
![Page 48: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/48.jpg)
![Page 49: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/49.jpg)
In or out?
![Page 50: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/50.jpg)
M.C. Escher
![Page 51: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/51.jpg)
Seeing faces
![Page 52: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/52.jpg)
Seeing faces • Face recognition is very special and complex; it’s handled by the
temporal lobe of the brain
• We don’t just see faces, we recognize different patters, facial expressions, familiarities, emotions, etc; as they all play an important role in our society.
• Our brain unconsciously look for faces everywhere, as we gain major information from faces in our culture.
• Face recognition is affected by visual triggers and cultural experiences
• Sometimes due to brain damage, face perception can be lost – prosopagnosia (face blindness)
![Page 53: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/53.jpg)
The Mars face
![Page 54: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/54.jpg)
![Page 55: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/55.jpg)
![Page 56: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/56.jpg)
Double images
![Page 57: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/57.jpg)
![Page 58: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/58.jpg)
Rubin’s vase
![Page 59: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/59.jpg)
Musician or a girl's face?
![Page 60: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/60.jpg)
Young girl or old woman?
![Page 61: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/61.jpg)
Double images based on earlier experiences
![Page 62: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/62.jpg)
Double images based on earlier experiences
• We see with our brain, earlier experiences, expectations, culture, etc…
• People with different earlier experiences and imprints see different images
• Possible factors: • Culture • Religion, belief systems • Age • Gender • Environment • Current emotions - “You may be an undigested bit of beef…” (Dickens)
![Page 63: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/63.jpg)
Old man's face or two lovers kissing?
![Page 64: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/64.jpg)
Cultural
![Page 65: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/65.jpg)
Environment
![Page 66: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/66.jpg)
Age
![Page 67: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/67.jpg)
Age, cultural
![Page 68: OPTICAL ILLUSIONS - BioVis · • Studying optical illusions helps us to understand deeply how our vision and brain work . Brightness-contrast illusions . Brightness-contrast illusions](https://reader033.vdocuments.mx/reader033/viewer/2022050601/5fa89e8d700e012241736205/html5/thumbnails/68.jpg)
Don’t forget your own filters and limitations,
and remember that perhaps you are just fooled.