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An empirical basis for Mach bands.

ABSTRACT: Mach bands, the illusory brightness maxima and minima perceived at the initiation and termination of luminance gradients, respectively, are generally considered a direct perceptual manifestation of lateral inhibitory interactions among retinal or other lower order visual neurons. Here we examine an alternative explanation, namely that Mach bands arise as a consequence of real-world luminance gradients. In this first of two companion papers, we analyze the natural sources of luminance gradients, demonstrating that real-world gradients arising from curved surfaces are ordinarily adorned by photometric highlights and lowlights in the position of the illusory bands. The prevalence of such gradients provides an empirical basis for the generation of this perceptual phenomenon.

SUBMITTER: Lotto RB

PROVIDER: S-EPMC21848 | biostudies-literature | 1999 Apr

REPOSITORIES: biostudies-literature

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An empirical basis for Mach bands.

Lotto R B RB Williams S M SM Purves D D

Proceedings of the National Academy of Sciences of the United States of America 19990401 9

Mach bands, the illusory brightness maxima and minima perceived at the initiation and termination of luminance gradients, respectively, are generally considered a direct perceptual manifestation of lateral inhibitory interactions among retinal or other lower order visual neurons. Here we examine an alternative explanation, namely that Mach bands arise as a consequence of real-world luminance gradients. In this first of two companion papers, we analyze the natural sources of luminance gradients, ...[more]

PMID: 10220450

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