Contributions to Viperlib
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Sarcone's ellipses
File Size: 4Kb
Resolution: 528x145
The Sarcone elliptical illusion is an optical illusion of relative size perception. Th...
Motion defined square
File Size: 33Kb
Resolution: 500x310
Play animation to make the square pop out from the background.
Motion defined 3D surface
File Size: 213Kb
Resolution: 640x490
Play animation to see a 3D surface pop out in depth. Note how the surface quickly disap...
Inverting surface
File Size: 287Kb
Resolution: 662x576
Most observers see the region under the arrow as concave. This demonstrates the percept...
Inverting contour surface
File Size: 120Kb
Resolution: 648x576
This demonstrates the perceptual bias for seeing surfaces face up rather than down. Pla...
The kinetic depth effect
File Size: 25Kb
Resolution: 432x396
Play animation to see the object pop out in depth.
Impossible contour surface
File Size: 258Kb
Resolution: 662x612
Perceptual bias for seeing surfaces face up can be overridden locally by T-junctions. M...
Ground attachment bias
File Size: 80Kb
Resolution: 490x360
Cylinders appear to be of unequal size because of bias to interpret objects attached to...
60-bizzarre dog
File Size: 41Kb
Resolution: 425x500
How many dogs can you count? (Impossible figure.)
Attend-o-movie from geoff boynton
File Size: 113Kb
Resolution: 570x570
The effects of spatial attention on responses in early visual areas. Subjects were aske...
Cow 3d
File Size: 19Kb
Resolution: 242x349
Construct your own desktop hollow-face illusion! (Note that the cow's face is hollow.) ...
The Perception of Visual Objects
File Size: 198Kb
Resolution: 570x570
Object recognition and higher-order visual processing. (Click on a blue bubble to take ...
Cafe wall
File Size: 7Kb
Resolution: 640x375
The cafe wall illusion, so called because the first time this illusion was spotted was ...
Colour after effect
File Size: 29Kb
Resolution: 883x397
Colour after-effect. Stare at the dot in the centre of the four coloured squares for ...
Binocular Rivalry
File Size: 2694Kb
Resolution: 112x112
This tutorial provides an introductory exploration of binocular rivalry.
Textandback2
File Size: 101Kb
Resolution: 773x581
The right-hand column illustrates how the left-hand column might look to a colour-blind...
Visualjitter
File Size: 256Kb
Resolution: 570x570
Visual Jitter demo. Fixate centre of pattern and adapt for 15 seconds. Click yellow dis...
Slalom
File Size: 76Kb
Resolution: 570x570
The demo simulates locomotion in a straight path across a ground plane in real time. Wh...
Motion Transparency 1
File Size: 38Kb
Resolution: 419x417
The two gratings slide past each other when the lightness of the intersections is compa...
Square illusion6
File Size: 45Kb
Resolution: 570x570
Humans consistently err in their percepts of rotational motion viewed through an apertu...
Sakai
File Size: 14Kb
Resolution: 620x568
The upper row squares (in both halves of the figure) are actually the same colour as th...
Ringcontrastdfromdonmacleod
File Size: 88Kb
Resolution: 1200x900
Demonstration of colour contrast: the inner and outer blue rings are the same colour. ...
Helen3
File Size: 17133Kb
Resolution: 570x570
Classic film footage of monkey Helen -- a monkey whose visual cortex was totally remove...
Size-contrast illusion with coins
File Size: 54Kb
Resolution: 960x720
The size-contrast (Titchner/Ebbinghaus) illusion is a powerful illusion of both size an...
Beuchet Chair Video
File Size: 18Kb
Resolution: 256x144
This short video shows how the chair is laid out. Thanks to Frans Verstraten for the v...
Movement detection in Blindsight
File Size: 18130Kb
This video was recorded by Larry Weiskrantz and John Barbur. It shows GY indicating the...
Beuchet Chair
File Size: 157Kb
Resolution: 701x868
A compact version of the Ames room where misperception of distance leads to improbable ...
Healinggrid
File Size: 94Kb
Resolution: 646x402
Healing Grid Illusion: for more details, see Extra Information.
Visual Perception of Motion
File Size: 211Kb
Resolution: 570x570
Motion processing. (Click on a blue bubble to take you to a new section, then use the a...
Beuchet Chair
File Size: 156Kb
Resolution: 787x1050
A compact version of the Ames room where misperception of distance leads to improbable ...
Confusing Stair
File Size: 60Kb
Resolution: 760x472
This is an impossible structure, there are many impossible structures in this photo, lo...
Horse2
File Size: 31Kb
Resolution: 206x182
Movie demonstrating that biological motion can be interpreted when the stimuli are defi...
Maevectorsum
File Size: 380Kb
Resolution: 570x570
A moving random pixel array consisting of two sheets moving perpendicularly in transpar...
Wanage1
File Size: 17Kb
Resolution: 512x512
The outer ring seems to expand and the inner ring seems to contract. The rings also app...
Hermannsinus2
File Size: 82Kb
Resolution: 570x570
The illusory spots of the Hermann grid disappear totally if a simple wiggle is introduc...
Hermannsinus
File Size: 136Kb
Resolution: 570x570
The illusory spots of the Hermann grid disappear totally if a simple wiggle is introduc...
Visual Areas in the Brain
File Size: 58Kb
Resolution: 512x451
Approximate positions of area V1 and some of the extrastriate visual areas in the human...
Coherence
File Size: 69Kb
Resolution: 570x570
Plaids: the two gratings cohere into a plaid when both have high contrast. But when th...
Motion Transparency 2
File Size: 40Kb
Resolution: 412x421
The left display moves as a plaid, and the right as components sliding past each other....
Sarcone's ellipses
File Size: 962Kb
Resolution: 2717x2717
This is an optical illusion of relative size perception. By effect of assimilation, th...
Development in the visual cortex
File Size: 64570Kb
Resolution: 570x570
Development in the visual cortex.
Bachshepardtables
File Size: 63Kb
Resolution: 570x570
Compare the two tables in the neighbouring figure. How do size and shape of the two tab...
Zenshin2
File Size: 35Kb
Resolution: 512x512
In this illusion, the rings appear to rotate when fixating on the centre and moving tow...
Craik-movie
File Size: 105Kb
Resolution: 570x570
A demonstration of the Craik-Obrien-Cornsweet Effect