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Rob van Lier, PhD
Associate Professor


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<<A few illusions>>

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a double neon color

Dancing Shapes Con-fusing Contours catching patches rivalry Afterimage filling-in face

A Double Neon Color Illusion
Van Lier (2002)

When two neon-coloured illusory bands overlap each other, the filling-in at the region of overlap is perceived to be different from those of the overlapping bands, resulting in an additional illusory shape at the region of overlap.

In Figure 1 and 2 two coloured examples of displays with overlapping neon bands are shown. Each display consists of four overlapping neon-coloured bands. The perceived lightness at the regions of overlap appears to be different from the lightness of the overlapping bands. The overlapping yellow neon bands (1) result in a darker overlapping region whereas overlapping blue neon bands (2) result in a lighter overlapping region.

At the Perception website these and various other colour examples can be seen.

See also a presentation of Daniel Dennett talking about this illusion here (TED talk)
at about 16:15 minutes or here (Same TED Talk with Dutch tranlations), or here at about 36 minutes.

D.Dennett TED