View full lesson: http://ed.ted.com/lessons/why-do-we-see-illusions-mark-changizi

Why can't our extremely complex eyes render simple optical illusions? Surprise, surprise -- it comes back to the brain, which has only evolved to encounter natural stimuli. At TEDYouth 2012, Mark Changizi explains how the brain reckons with optical illusions.

Talk by Mark Changizi.

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