Macular Pigment and Visual Performance in Low-Light Conditions

Abstract

Macular pigment appears to enhance visual function in low-light conditions. Based on the results of this study, it can be said that MP extends the range of foveal vision into lower light. Additionally, MP appears to enhance dark adaptation kinetics, which suggests that increased MPOD leads to more efficient photopigment regeneration. The findings of the color detection portion of the study are suggestive of an active compensatory mechanism that offsets absorption by MP in order to maintain normal color perception.

Nitric Oxide and Lutein: Function, Performance, and Protection of Neural Tissue

“…It could be that the two molecules form a system, whereby (due presumably to a reduction in oxidative-stress-based visual cycle inhibition) the visual cycle is allowed to operate at high efficiency. This idea was postulated recently by Stringham et al [61], whose subjects exhibited significantly faster dark adaptation as a function of MPOD. A significant enhancement of physiological function by L has also been demonstrated for speed of visual processing [62,63], where subjects with higher MPOD were shown to have significantly higher critical flicker fusion (CFF) thresholds.…”

Enrichment of Macular Pigment Enhances Contrast Sensitivity in Subjects Free of Retinal Disease: Central Retinal Enrichment Supplementation Trials – Report 1

“…In consideration of our finding of enhanced CS following enrichment of MP in the active group, this idea was first introduced by Stringham et al, 52 who found a relationship between MPOD and CS for a slightly higher spatial frequency (10 cycles/deg). The idea was subsequently expanded upon, 53 and further supported by the suggestion of a plausible molecular mechanism involving the interplay of retinal carotenoids and nitric oxide, 54 whereby increased macular carotenoids facilitate the ability of nitric oxide to increase the signal-to-noise ratio of horizontal cells that serve center-surround receptive fields. 55 An important distinction between the findings of our study and those of previous investigators is that we observed improvements in CS that were commensurate with MP augmentation, which suggests that the observed benefits are, indeed, attributable to observed increases in MP over the study period (and not attributable to interindividual variability in factor[s] related to MP).…”

Lutein and Zeaxanthin Isomers in Eye Health and Disease

“…For more than a century, it has been speculated that MP plays a role in enhancing visual performance; in the past two decades, observational studies have, indeed, suggested that MP influences performance on visual tasks (for a recent review and critical discussion, see 65, 173). New observational, experimental, and clinical evidence (summarized below and in Table 1) suggests that L, Z, and/or meso-Z could improve performance on tasks involving several different aspects of the visual system, from the eye to the brain, in both young, healthy people and people with ocular diseases.…”

“…High MP levels may also enhance visual performance in moderate and bright lights by increasing the range over which vision-related tasks can be comfortably performed (173). For example, it has been estimated that increasing MPOD at a 1° diameter around the center of the fovea by 0.3 density units would roughly double the intensity of white light necessary to produce visual discomfort.…”