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      What Dictionaries and Optical Illusions Say About Our Brains

      Cognitive scientist Mark Changizi does not bother with how the brain accomplishes a task, but rather why it performs the function in the first place.

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      What Dictionaries and Optical Illusions Say About Our Brains
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      Credits: COURTESY OF RENSSELAER POLYTECHNIC UNIVERSITY

      What Dictionaries and Optical Illusions Say About Our Brains

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      • FLOWING LUMINANCE: Bobbing your head toward the center leads to the bright patch expanding outward. Moving away does the opposite. This illusion was created by Mark Changizi in 2003. COURTESY OF MARK CHANGIZI
      • OPTIC BLURS: If you bob your head toward the center of this image, the blurred markings will begin flowing outward “too fast.” This illusion was created by Mark Changizi in 2003. COURTESY OF MARK CHANGIZI
      • MOVING OPTIC STREAKS: The blurs appear to be in motion. Those with the longer tails seem to be moving faster. This illusion appears for the first time in the May issue of Cognitive Science (Changizi et al., 2008)... COURTESY OF MARK CHANGIZI
      • BULGING GRID: Moving you face toward the image gives it the appearance of bulging. This illusion was first described by Chris Foster and Eric L. Altschuler in 2001.
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      • TILTING RECTANGLE: The greater contrast portion (left side) of the rectangle at the center of the picture appears tilted toward you. This illusion appears for the first time in the May issue of Cognitive Science (Changizi et al., 2008)... COURTESY OF MARK CHANGIZI
      • STATIC BULGING GRID: The center of the grid appears to bulge, bowing outwards. This illusion appears for the first time in the May issue of Cognitive Science (Changizi et al., 2008). COURTESY OF MARK CHANGIZI
      • CONTRASTING ELLIPSES: The black ellipse on the left looks larger because of the more noticeable difference between its color and that of the background. This illusion was first described by psychologist Edward J... COURTESY OF MARK CHANGIZI
      • THE ASSIMILATION ILLUSION: The bars on the left appear do not appear as bright as the thicker bars on the right. This effect was first described by American psychologist Harry Helson in 1963. COURTESY OF MARK CHANGIZI
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      • THE EBBINGHAUS ILLUSION: Even though both are the same size, the red circle on the left appears larger that the one on the right. It was discovered by German psychologist Hermann Ebbinghaus. COURTESY OF MARK CHANGIZI
      • THE ORBISON ILLUSION: The squares in the grid should appear to be distorted. This effect was first described by German psychologist Walter Ehrenstein in 1925. COURTESY OF MARK CHANGIZI
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      • FLOWING LUMINANCE:
      • OPTIC BLURS:
      • MOVING OPTIC STREAKS:
      • BULGING GRID:
      • TILTING RECTANGLE:
      • STATIC BULGING GRID:
      • CONTRASTING ELLIPSES:
      • THE ASSIMILATION ILLUSION:
      • THE EBBINGHAUS ILLUSION:
      • THE ORBISON ILLUSION:
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