Abstract:
:Although current theories of color vision differ in many respects, they all assume the existence of a uniquely defined neutral point in chromaticity space. It generally is assumed that this point satisfies several criteria simultaneously. One of these criteria is that it is perceived as achromatic. A further criterion shared by most theories is the structural assumption that lines in chromaticity space of constant hue converge on the neutral point. The basic assumption that these two criteria coincide is clearly true for isolated spots of light presented in darkness, and it usually is taken for granted that this coincidence generalizes to more complex visual stimuli. Here, we show that this is not the case. Our experiments with infields in chromatic surrounds revealed that the point in chromaticity space that appears gray is clearly different from the point on which lines of constant hue converge. A plausible interpretation of this apparently paradoxical finding in terms of color scission is proposed.
journal_name
Proc Natl Acad Sci U S Aauthors
Ekroll V,Faul F,Niederée R,Richter Edoi
10.1073/pnas.192216699keywords:
subject
Has Abstractpub_date
2002-10-01 00:00:00pages
13352-6issue
20eissn
0027-8424issn
1091-6490pii
192216699journal_volume
99pub_type
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