Scope The neural efficiency hypothesis for lutein (L) and zeaxanthin (Z) suggests that higher levels of L+Z in the central nervous system (CNS) are predictive of stronger stimulus‐specific brain responses. Past research suggests that supplementing L+Z can improve neural processing speed and cognitive function across multiple domains, which supports this hypothesis. The purpose of this study is to determine the extent to which CNS L+Z levels predict brain responses using an attentionally taxing task. Methods and results Macular pigment optical density (MPOD) is measured at baseline in 85 participants ranging in age from 18–92 years. Brain activation is measured using dense array electroencephalography. Stimuli evoking the signal include a grating array of vertical bars, oscillating at four driving frequencies. Significant stimulus‐specific interactions are detected between attend condition, location, and age (p < .002) for unattended image locations, and between age and location (p < .008) for attended locations. Although no differences are found across age by MPOD, this measure is found to be predictive of neural power at parafoveal bar locations (R2 .080). Conclusion CNS L+Z status is related to differences in brain activation in conditions designed to stress visual attention. These differences are strongest for older subjects.

Lutein (L) and zeaxanthin (Z) are incorporated into the neural retina as macular pigment (MP), which is a biomarker of L+Z distributed throughout the cortex. Cortical L+Z may have the ability to improve cognitive function. The purpose of this study was to determine whether or not MP relates to cognition in healthy elders and elders with mild cognitive impairment (MCI). 41 elders (M = 75.5 ± 6.3 years) participated. 15 of the 41 elders met criteria for MCI. MP density was measured psychophysically, and cognition was assessed via the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Visual processing speed was also measured. MP density was related to cognitive function in the visuospatial (r = 0.43, p < 0.05) and attentional (r = 0.47, p < 0.05) domains of the RBANS in elders with MCI, but not in unimpaired elders. Elders with MCI were also less sensitive to flicker. These results suggest that MP's relationship to cognition varies with cognitive impairment.