Variability of chromatic visual sensitivity: discrimination according to daily shifts

ABSTRACT

This study aimed to verify the daily variation in the chromatic visual sensitivity of healthy subjects. The study included 35 male adults, aged between 20 and 40 years old (M = 24.97; SD = 4.9). The evaluation of color perception was made through the Cambridge Colour Test, using the Trivector and Ellipse tests. The Pittsburgh Sleep Quality Index, the Sleep Diary, and the Karolinska Sleepiness Scale were used to assess possible influences of circadian rhythmicity. Significant differences were found for the protan confusion axes at 8 am (Z = 2.9; p = 0.012) and at 8 pm (Z = 2.8; p = 0.01), and deutan at 8 am (Z = 2.6; p = 0.028) and at 8 pm (Z = 3.5; p = 0.001), and for the A1 ellipses areas at 8 am (Z = 2.5; p = 0.037) and at 8 pm (Z = 2.4; p = 0.018), and A3 at 8 am (Z = 2.1; p = 0.039) and at 8 pm (Z = 3.6; p = 0.001). Thus, chromatic sensitivity can be characterized by an inverted U-shaped curve, with peak sensitivity in the morning and evening, and attenuation in the afternoon.

KEYWORDS:

• Melanopsin
• daily rhythm
• color vision
• Cambridge colour test

Acknowledgments

National Council for Scientific and Technological Development http://www.cnpq.br/.

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contributions

Maria Thalita Cardoso Rezende (Rezende, MTC); Bruna Gabrielli Damascena de Figueiredo (Figueiredo, BGD); Thiago Augusto de Souza Bonifácio (Bonifácio, TAS); Natanael Antonio dos Santos (Santos, NA); Michael Jackson Oliveira de Andrade (Andrade, MJO)

Rezende, MTC: data interpretation, study design, writing and critical review of the article; Figueiredo, BGD: data interpretation, study design, writing and critical review of the article; Bonifácio, TAS: data interpretation, study design, writing and critical review of the article; Santos, NA: data analysis and interpretation, critical review of the article. The entire author approved the final version of the manuscript; Andrade, MJO: outline, study design, statistical analysis and critical review of the article.

Additional information

Funding

This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.