Investigating the effects of lutein and zeaxanthin on neural activation and visual processing
Thorne, Sarah Anna
MetadataShow full item record
Introduction: The purpose of the present study was to investigate the effects of lutein (L) and zeaxanthin (Z) supplementation on steady-state visual evoked potentials (SSVEPs) and behavioral measures of visual processing. Method: Fifty-five participants ranging in age from 65-99 years and 61 participants ranging in age from 18-30 years were recruited. In a double-blind placebo-controlled design, participants were randomized into a supplemental group that received either 10 mg of L and 2 mg of Z (n = 62) or placebo (n = 25). LZ status was determined by measuring macular pigment optical density (MPOD) and serum. Independent t-tests were used to compare difference scores for steady-state visual evoked potentials (SSVEPs), temporal contrast sensitivity function (TCSF), critical flicker fusion thresholds (CFF), reaction time (RT), processing speed, and psychomotor speed. Results: Cross-sectional differences based on MPOD were observed for SSVEPs in both younger and older adults. In response to the intervention, differences existed in older adults in the supplement group for SSVEPs compared to placebo. For younger participants, no differences were found in the SSVEPs but significant differences were found for the TCSF based on supplementation status. Conclusion: L+Z supplementation influences processing of visual stimuli.