Specificity of the chromatic noise influence on the luminance contrast discrimination to the color vision phenotype

Author(s):Show less -

Silva Sousa, Bruna Rafaela ^[1] ; Medeiros Goncalves Loureiro, Terezinha ^[2] ; Kilpp Goulart, Paulo Roney ^[3] ; Tentes Cortes, Maria Izabel ^[4] ; Costa, Marcelo Fernandes ^[5] ; Oliveira Bonci, Daniela Maria ^[5] ; Portnoi Baran, Luiz Claudio ^[5] ; Hauzman, Einat ^[5] ; Ventura, Dora Fix ^[5] ; Miquilini, Leticia ^[3] ; Souza, Givago Silva ^{[2, 1]}

Affiliation

^[1] Univ Fed Para, Nucleo Med Trop, Av Generalissimo Deodoro 92, BR-66055240 Belem, Para - Brazil

^[2] Univ Fed Para, Inst Ciencias Biol, Belem, Para - Brazil

^[3] Univ Fed Para, Nucleo Teoria & Pesquisa Comportamento, Belem, Para - Brazil

^[4] Univ Fed Amapa, Ctr Ciencias Saude, Macapa - Brazil

^[5] Univ Sao Paulo, Inst Psicol, Sao Paulo - Brazil

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 10, n. 1 OCT 21 2020.
• Web of Science Citations: 0

Abstract

Many studies have examined how color and luminance information are processed in the visual system. It has been observed that chromatic noise masked luminance discrimination in trichromats and that luminance thresholds increased as a function of noise saturation. Here, we aimed to compare chromatic noise inhibition on the luminance thresholds of trichromats and subjects with severe deutan or protan losses. Twenty-two age-matched subjects were evaluated, 12 trichromats and 10 with congenital color vision impairment: 5 protanopes/protanomalous, and 5 deuteranopes/deuteranomalous. We used a mosaic of circles containing chromatic noise consisting of 8 chromaticities around protan, deutan, and tritan confusion lines. A subset of the circles differed in the remaining circles by the luminance arising from a C-shaped central target. All the participants were tested in 4 chromatic noise saturation conditions (0.04, 0.02, 0.01, 0.005 u ` v ` units) and 1 condition without chromatic noise. We observed that trichromats had an increasing luminance threshold as a function of chromatic noise saturation under all chromatic noise conditions. The subjects with color vision deficiencies displayed no changes in the luminance threshold across the different chromatic noise saturations when the noise was composed of chromaticities close to their color confusion lines (protan and deutan chromatic noise). However, for tritan chromatic noise, they were found to have similar results to the trichromats. The use of chromatic noise masking on luminance threshold estimates could help to simultaneously examine the processing of luminance and color information. A comparison between luminance contrast discrimination obtained from no chromatic and high-saturated chromatic noise conditions could be initially undertaken in this double-duty test. (AU)

• FAPESP's process: 14/26818-2 - Development and implementation of visual evaluation methods: clinical applications and animal models
• Grantee: Dora Selma Fix Ventura
• Support Opportunities: Research Projects - Thematic Grants