Modeling the Effect of Macular Pigment Enhancement on Mesopic Vision in Degraded Visual Environments (DVE) in Artificial Light

摘要

The macular pigment is an accumulation of the dietary carotenoids lutein, zeaxanthin, and mezo-zeaxanthinthroughout the retina but principally in the region corresponding to the central 15° of the visual field. Sincethe macular pigment absorbs light in the 400 to 520 nm range, it is a spectral filter over the photoreceptors,attenuating the incident light in the macular pigment absorption spectrum. The between-subject average macularpigment optical density is about 0.2 to 0.6 log units with a range reportedly between 0 to 1.5 log units dependingon the sampled population. Some people can increase their macular pigment optical density by increasingtheir consumption of lutein and zeaxanthin, which may have consequences for visibility in degraded visualenvironments (DVE). Specifically, nutritional and dietary interventions have produced statistically significantenhancements in such visual tasks as low contrast target detection, contrast sensitivity, glare resistance andrecovery, etc. The question is whether these changes are operationally meaningful. The present paper modelsmacular pigment optical density effects on mesopic vision using the current CIE recommendation for scotopicto-photopic weighting to define mesopic spectral sensitivity. Since the scotopic spectrum overlaps that of themacular pigment more than does the photopic spectrum, the effect of the macular pigment increases as visiontransitions from photopic-to-scotopic conditions. Our mesopic visibility model, an elaboration of our previouslyreported photopic and scotopic models, captures this effect and applies it to current light sources common incultural lighting and to reectance spectra we previously evaluated and reported.