Is discrimination enhanced at the boundaries of perceptual categories? A negative case.
Proc Biol Sci
; 281(1785): 20140367, 2014 Jun 22.
Article
en En
| MEDLINE
| ID: mdl-24807255
ABSTRACT
The human visual system imposes discrete perceptual categories on the continuous input space that is represented by the ratios of excitations of the cones in the retina. Is discrimination enhanced at the boundaries between perceptual hues, in the way that discrimination may be enhanced at the boundaries between speech sounds in hearing? In the chromaticity diagram, the locus of unique green separates colours that appear yellowish from those that appear bluish. Using a two-alternative spatial forced choice and an adapting field equivalent to the Daylight Illuminant D65, we measured chromatic discrimination along lines orthogonal to the locus of unique green. In experimental runs interleaved with these performance measurements, we obtained estimates of the phenomenological boundary from the same observers. No enhancement of objectively measured discrimination was observed at the category boundary between yellowish and bluish hues. Instead, thresholds were minimal at chromaticities where the ratio of long-wave to middle-wave cone excitation was the same as that for the background adapting field.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Percepción de Color
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Células Fotorreceptoras Retinianas Conos
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Discriminación en Psicología
Tipo de estudio:
Prognostic_studies
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Qualitative_research
Límite:
Female
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Humans
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Male
Idioma:
En
Año:
2014
Tipo del documento:
Article