Why can you hear some sounds two different ways, depending on which word you’re looking at? Why do electrical outlets sometimes look like a face? How can you have rich visual experience with your eyes closed? Are some crosswalk buttons fake? Why are some pictures interpretable only once you’ve been told what to look for? And although brains are often celebrated for their parallel processing, what should they really be celebrated for? Tune in to learn what happens when the raw facts of the world collide with your expectations.

Episode Audio

Episode Video

More Information:
Eagleman DM (2011). Incognito: The Secret Lives of the Brain. New York: Pantheon.

Deutsch D. (1972). Octave generalization and tune recognition. Perception & Psychophysics. 11, 411-412.

Gegenfurtner KR, Bloj M, Toscani M. (2015). The many colours of ‘the dress’. Current Biology. 2015 Jun 29;25(13):R543-4.

Lafer-Sousa R, Hermann KL, Conway BR. (2015). Striking individual differences in color perception uncovered by ‘the dress’ photograph. Current Biology. 2015 Jun 29;25(13):R545-6.

Wallisch P. (2017). Illumination assumptions account for individual differences in the perceptual interpretation of a profoundly ambiguous stimulus in the color domain:“The dress”. Journal of Vision. 2017 Apr 1;17(4):5-5.

The Necker cube:

What do these blobs represent?

The McGurk effect:

The blobs above represent a dalmatian dog sniffing something on the sidewalk. His head is to the left and his rear to the right.


"David Eagleman offers startling lessons.... His method is to ask us to cast off our lazy commonplace assumptions.
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"What Eagleman seems to be calling for is a new Enlightenment."
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"David Eagleman is the kind of guy who really does make being a neuroscientist look like fun."
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"[A] neuroscientist and polymath."
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"David Eagleman may be the best combination of scientist and fiction-writer alive."
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"Eagleman has a talent for testing the untestable, for taking seemingly sophomoric notions and using them to nail down the slippery stuff of consciousness."
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"A popularizer of impressive gusto...[Eagleman] aims, grandly, to do for the study of the mind what Copernicus did for the study of the stars."
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