William Oliver1, Lisa M Renzi-Hammond2,3, S Anna Thorne2,4, Brett Clementz1, L Stephen Miller5, Billy R Hammond2,3. 1. Clinical and Cognitive Neuroscience Laboratory, Behavioral and Brain Sciences Program, Department of Psychology, The University of Georgia, Athens, GA, 30602, USA. 2. Vision Sciences Laboratory, Behavioral and Brain Sciences Program, Department of Psychology, The University of Georgia, Athens, GA, 30602, USA. 3. Human Biofactors Laboratory, Institute of Gerontology, Department of Health Promotion and Behavior, The University of Georgia, Athens, GA, 30602, USA. 4. Athens Community Council on Aging, Athens, GA, 30602, USA. 5. Neuropsychology and Memory Assessment Laboratory, Clinical Psychology Program, Department of Psychology, The University of Georgia, Athens, GA, 30602, USA.
Abstract
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.
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.