Mind Your Heart: A Mindful Eating and Diet Education eHealth Program.

OBJECTIVE: Examine user perceptions of the Mind Your Heart (MYH) program, a mindful eating and nutrition education program delivered via an eHealth system. METHODS: Sixteen participants (41.5 ± 13.1 years) completed sample MYH lessons over 3 weeks. We examined changes in mindfulness from the State Mindfulness Scale via text messages sent 3 times per week. We assessed MYH user perceptions in a semistructured interview after 3 weeks. Analyses included Spearman's correlation, repeated measures ANOVA, and thematic analysis. RESULTS: State Mindfulness Scale scores were significantly improved (F[1,15] = 5.35, P = 0.01) from week 1 (M = 2.28 ± 0.80) to week 3 (M = 2.75 ± 1.04). Four themes emerged: (1) MYH is supportive of health goals, (2) text messages act as an intervention, (3) facilitators or inhibitors of use, and (4) enhancing engagement. CONCLUSIONS AND IMPLICATIONS: Based on participant feedback, the final version of MYH should include example-based learning to translate abstract concepts like mindful eating into action.

Contrast sensitivity functions measured using simple optics and computer testing.

PURPOSE: Contrast sensitivity function (CSF) testing is a common approach to assessing clinical changes to specific aspects of spatial vision. Different stimulus presentations and testing procedures, however, yield significant differences in CSF curves that are more a feature of the method than the observer. In this study, we designed a simple optical device for measuring CSF that could be directly calibrated and compared with a commonly used computer-based system. METHODS: Twenty-one participants (M = 28.95 ± 10.34 years; 66.7% female; 81.0% non-Hispanic White; best corrected visual acuity 6/9 or better) provided photopic CSFs (from measurements at 1.6, 3.2, 8, 16 and 24 cycles per degree, with spatial frequency presentation randomised) using both the Metropsis test platform and a simple optical device over two test sessions (one session/method, randomised, counterbalanced) separated by 1-7 days. The optical system used 520 nm lasers that were made Lambertian using two integrating spheres with a 3.5° circular exit port. These beams were combined with a beam splitter that allowed constant measurement of light output and contrast modulation using sine-wave gratings on glass. In Metropsis, 2° Gabor stimuli were presented for 0.5 s with either a vertical or a horizontal orientation via a two-alternative forced choice paradigm with contrast modulated until four (first) and eight (last) reversals were complete. RESULTS: Both methods took approximately the same amount of time to generate a CSF and yielded curves that were consistent with past studies using similar methods but different from each other. The optical system showed a 3.5 times higher maximum sensitivity and yielded higher test-retest reliability. CONCLUSIONS: Using simple optics to measure CSF yields low noise, high sensitivity and reliability. The ability to calibrate the stimuli directly is an advantage over computer-based methods.

A Dietary Strategy for Optimizing the Visual Range of Athletes.

Visual range is quantified by assessing how far one can see clearly (an ability crucial to many athletes). This ability tends to vary significantly across individuals despite similar personal characteristics. We hypothesize that the primary driver of these differences is the individual response to scattered short-wave light in the environment moderated by the dietarily derived retinal pigments lutein and zeaxanthin.

The effect of a short-wave filtering contact lens on color appearance.

We assessed the effect of a contact lens that filters short-wavelength (SW) visible light on color appearance. These effects were modeled and measured by direct comparison to a clear contact lens. Sixty-one subjects were enrolled, and 58 completed as cohort; 31 were 18 to 39 years old (mean ± SD, 29.6 ± 5.6), 27 were 40 to 65 years old (50.1 ± 8.1). A double-masked contralateral design was used; participants randomly wore a SW-filtering contact lens on one eye and a clear control lens on the other eye. Subjects then mixed three primaries (including a short-wave primary, strongly within the absorbance of the test lens) until a perceived perfect neutral white was achieved with each eye. Color appearance was quantified using chromaticity coordinates measured with a spectral radiometer within a custom-built tricolorimeter. Color vision in natural scenes was simulated using hyperspectral images and cone fundamentals based on a standard observer. Overall, the chromaticity coordinates of matches that were set using the SW-filtering contact lens (n = 58; x = 0.345, y = 0.325, u' = 0.222, v' = 0.470) and clear contact lens (n = 58; x = 0.344, y = 0.325, u' = 0.223, v' = 0.471) were not significantly different, regardless of age group. Simulations indicated that, for natural scenes, the SW-filtering contact lens that was evaluated changes L/(L+M) and S/(L+M) chromatic contrast by no more than -1.4% to +1.1% and -36.9% to +5.0%, respectively. Tricolorimetry was used to measure color appearance in subjects wearing a SW-filtering lens in one eye and a clear lens in the other, and the results indicate that imparting a subtle tint to a contact lens, as in the SW-filtering lens that was evaluated, does not alter color appearance for younger or older subjects. A model of color vision predicted little effect of the lens on chromatic contrast for natural scenes.

The Influence of HEV-Filtering Contact Lenses on Behavioral Indices of Glare.

OBJECTIVES: We assessed the effects of a HEV-filtering contact lens on positive dysphotopsia (halos and starbursts) and a behavioral index of scatter measured using two-point light thresholds. These effects were assessed by direct comparison to a clear (i.e., non-HEV filtering) contact lens tested in the fellow eye. METHODS: Sixty-one subjects were randomized and fit with study lenses and 58 subjects completed the study. A double-masked contralateral design was used. Subjects were randomized to test lens-OD, control lens-OS, or vice versa. Participants were exposed to a point source of broadband simulated sunlight (a 403-nm condition was also tested) that created the appearance of halos/starbursts. The degree of dysphotopsia was measured as the diameter of broadband and violet-induced halos, and broadband light-induced starbursts. Two-point thresholds were assessed as the minimum resolvable distance between two pinpoints of light. RESULTS: The HEV-filtering lens was statistically superior ( P <0.0001) to the clear lens in all the conditions tested. The HEV-filtering lens significantly reduced halo diameter by 30%, starburst diameter by 23%, and resolvable distance in the two-point condition by 18% (white) and 30% (violet). CONCLUSIONS: HEV-filtering contact lenses can reduce some deleterious effects of bright broadband light by decreasing light scatter, halos, and starbursts.

Reduction of Glare Discomfort and Photostress Recovery Time Through the Use of a High-Energy Visible-Filtering Contact Lens.

OBJECTIVES: Glare discomfort (GDC) is the slight pain (discomfort) that arises when exposed to light that exceeds one's adaptive state. Such light can also cause a temporary loss in visual function (photostress, PS). We tested the hypothesis that filtering with a high-energy visible (HEV) light-filtering contact lens can reduce GDC and speed PS recovery time. METHODS: Sixty-one subjects were randomized and fit with study lenses and 58 subjects completed as cohort (20-65 years of age). A double-masked, randomized, contralateral design was used (HEV filter on one eye; control lens on the other). Participants were given a 5-s exposure to a broadband white photostressor. Video images were analyzed, and palpebral fissure size during exposure was measured, as was PS recovery time to a 2-degree mid-wave target. RESULTS: The HEV-filtering test lens was statistically superior ( P <0.0001) to the clear comparison contact lens with respect to the magnitude of squint (44.9% squint reduction) and photostress recovery time (24.3% faster recovery). CONCLUSIONS: High-energy visible light-filtering contacts can reduce GDC and speed PS recovery. Filtering HEV light before it is incident upon the retina is a natural strategy (e.g., by the lens and macular pigment) for attenuating some of the deleterious effects of bright broadband light.

Blue-Light Filtering Intraocular Implants and Darker Irises Reduce the Behavioral Effects of Higher-Order Ocular Aberrations.

PURPOSE: Higher order ocular aberrations (e.g. entopic scatter) arising from cornea and lens, decreases retinal image contrast by dispersing part of the image-forming optics over a broad retinal surface. Selective filtering of the light that is most susceptible to aberration (high-energy "blue" light) may reduce some of the behavioral effects. This was tested by comparing the performance of a blue-light filtering (BLF) vs a clear intraocular lens implant (IOL). METHODS: 52 participants with IOL (BLF: AlconSN60AT; clear: AlconSA60AT; N = 98 test eyes; M = 67.33 ± 7.48 years; 58.8% Female; 25.5% non-White) were recruited. Our outcome measure was based on the minimum resolvable distance between two points of light (two-point thresholds), formed using broadband xenon or isolated short-wave energy (425 nm). Iris color was measured by visual inspection and comparison against standard images. RESULTS: In the broadband condition, patients with BLF IOL had smaller two-point thresholds (M = 17.17 ± 5.71 mm; F[1,48] = 2.60; p = 0.045) than clear controls (M = 20.93 ± 10.22 mm). Similar improvements were found in the short-wave condition (MBLF=17.02 ± 5.30; Mclear=21.42 ± 10.99; p = 0.04). In the contralateral broadband comparison, eyes with the BLF had significantly smaller two-point thresholds (M = 18.10 ± 10.47 mm; t = -2.90, p < 0.001) than the clear IOL (M = 20.89 ± 10.61 mm). Similar effects were seen in the short-wave condition (MBLF=18.23 ± 9.88; Mclear = 21.06 ± 10.47; p = 0.001). Darker iris color was related to reduced scatter across IOL types, in both shortwave (F[2,48] = 4.62, p = 0.02) and broadband (F[2,48] = 5.27, p = 0.009) conditions. CONCLUSIONS: Anterior screening, be it by a darker iris or a BLF IOL, is directly related to decreases in two-point light thresholds.

Single Nucleotide Polymorphisms in CD36 Are Associated with Macular Pigment among Children.

BACKGROUND: High macular pigment optical density (MPOD) has been associated with improved eye health and better cognitive functions. Genetic variations have been associated with MPOD in adults. However, these associations between genetic variations and MPOD have not been studied in children. OBJECTIVES: This was a secondary analysis of the FK2 (Fitness Improves Thinking in Kids 2) trial (n = 134, 41% male). The aim was to determine differences in MPOD among children (aged 7-9 y) based on genetic variants that either are biologically relevant to lutein (L) and zeaxanthin (Z) accumulation or have been associated with MPOD in adults. METHODS: MPOD was measured using customized heterochromatic flicker photometry via a macular densitometer. DXA was used to assess whole-body and visceral adiposity. DNA was extracted from saliva samples and was genotyped for 26 hypothesis-driven single nucleotide polymorphisms and 75 ancestry-informative markers (AIMs). Habitual diet history was obtained via 3-d food logs completed by parents (n = 88). General linear models were used to compare MPOD between different genotypes. Principal component analysis was performed for the AIMs to account for ethnic heterogeneity. RESULTS: Children carrying ≥1 minor allele on ß-carotene-15,15'-monooxygenase (BCO1)-rs7501331 (T allele) (P = 0.045), cluster of differentiation 36(CD36)-rs1527483 (T allele) (P = 0.038), or CD36-rs3173798 (C allele) (P = 0.001) had significantly lower MPOD (range: 14.1%-26.4%) than those who were homozygotes for the major alleles. MPOD differences based on CD36-rs3173798 genotypes persisted after adjustment for dietary L and Z intake. CONCLUSIONS: The findings indicate that genetic variations of CD36 and BCO1 contribute to MPOD in children. The influence of genetic variation in CD36-rs3173798 persisted after adjusting for variation in dietary intake.This trial was registered at clinicaltrials.gov as NCT01619826.

Weight Status and Visceral Adiposity Mediate the Relation between Exclusive Breastfeeding Duration and Skin Carotenoids in Later Childhood.

BACKGROUND: Breastfeeding is associated with healthier weight and nutrient status in early life. However, the impact of breastfeeding on carotenoid status beyond infancy, and the influence of adiposity, are unknown. OBJECTIVES: The aim of the study was to retrospectively investigate the relation between breastfeeding and carotenoid status, and the mediating effect of weight status and adiposity on this relation, among school-age children. METHODS: This was a secondary analysis of baseline data collected from a randomized-controlled clinical trial. Children 7-12 y old (n = 81) were recruited from East-Central Illinois. DXA was used to assess visceral adipose tissue (VAT) and whole-body total fat percentage (%Fat; i.e., whole-body adiposity). Weight was obtained to calculate children's BMI percentiles. Skin carotenoids were assessed via reflection spectroscopy. Macular carotenoids were assessed as macular pigment optical density (MPOD). Dietary, birth, and breastfeeding information was self-reported by parents. RESULTS: Skin carotenoids were inversely related to %Fat (P < 0.01), VAT (P < 0.01), and BMI percentile (P < 0.01). VAT and BMI percentile significantly mediated this relation between exclusive breastfeeding duration and skin carotenoids, after adjustment for dietary carotenoids, energy intake, and mother education. CONCLUSIONS: Weight status and adipose tissue distribution mediate the positive correlation between exclusive breastfeeding duration and skin carotenoids among children aged 7-12 y. The results indicate the need to support breastfeeding and healthy physical growth in childhood for optimal carotenoid status.This trial was registered at clinicaltrials.gov as NCT03521349.

Temporal vision is related to cognitive function in preadolescent children.

The relation between visual processing speed (critical flicker fusion thresholds [CFF] and psychomotor reaction time) and higher-level cognitive function was assessed using a cross-sectional sample (n = 51) of 7 to 13-year-old preadolescent children. Data on visual processing speed (CFF and psychomotor reaction time) and cognitive function (Woodcock-Johnson III Tests of Cognitive Abilities) were collected. Woodcock-Johnson III composite standard scores (brief intellectual ability [BIA], cognitive efficiency, processing speed, and executive processes) were calculated to control for age in the cognitive variables. CFF was related to cognitive efficiency, r(46) = 0.26, p = 0.036, and executive processes, r(44) = 0.25, p = 0.05, and showed a trend toward relating to processing speed, r(46) = 0.19, p = 0.09. Both psychomotor reaction time measures (fixed and variable) were related to executive processes and global intelligence (BIA) such that higher cognitive scores were associated with shorter reaction times, rs ranged from -0.25 to -0.29, ps < 0.05. In addition, fixed reaction time was related to cognitive efficiency, r(47) = -0.26, p < 0.05. The small nature of many of these relations suggests that visual processing speed is only one of many possible influences on the higher cognitive function of children.

The effects of light scatter when using a photochromic vs. non-photochromic contact lens / Efectos de la dispersión luminosas al utilizar lentes de contacto fotocromáticas vs. no fotocromáticas

PURPOSE: To assess the visual effects of wearing both an activated and an inactivated photochromic contact lens, with a direct comparison to a non-photochromic contact lens worn in the fellow eye. This study focused on the visual effects of scatter quantified as the minimum distance between two points of light, and the diameter of the halo and starbursts that surround a bright white point source. METHODS: 60 subjects (aged 18-65 years) were measured in a contralateral design where lens type was randomly assigned, one type to each eye. During activated testing, all visual measures of both study lenses were made while each eye was illuminated by a violet (Lambdamax = 365, half bandwidth 20 nm) activator, which caused steady-state activation of the photochromic lens during the period of testing. Two-point thresholds were determined by measuring the minimum distance between two points of broadband xenon light. Glare geometry was measured using an aperture (∼ 4 mm) that created a bright point source of light 45 inches from the plane of the eye. Between the point source and subject, a centering precision caliper was used to measure lateral spread of halos (diffusion around the source) and visual spokes. The head was stabilized using an adjustable head-rest assembly and the eye was aligned and monitored with a bore camera. RESULTS: Compared to the non-photochromic lens, and based on the stimulus conditions used in these measurements, the activated and inactivated photochromic lens reduced the light spread using the two-point threshold technique by 32% and 19% respectively; the diameter of the halos were reduced by 44% and 16% respectively; and the spokes were narrowed by 39% and 20% respectively. Based on 95% confidence interval testing, these effects were all statistically significant (p < 0.05). CONCLUSIONS: These results are consistent with previous data showing that soft contact lenses with a photochromic additive can improve many aspects of visual function, consistent with their level or activation. Our past data focused on visual function under bright light conditions (e.g., glare disability, discomfort, photostress recovery and chromatic contrast) with an activated photochromic. In this study, we found differences even in the inactivated state, using less intense stimuli (10cd/m2 at the source). This suggests that the photochromic lens improves the effects of light scatter even at lower luminance

OBJETIVO: Evaluar los efectos visuales del uso de lentes de contacto con activación e inactivación fotocromática, mediante comparación directa con el uso de lentes de contacto no fotocromáticas en el ojo contralateral. Este estudio se centró en los efectos visuales de la dispersión, cuantificada mediante la distancia mínima entre dos puntos luminosos, y el diámetro del halo y los destellos que rodean a una fuente fija blanca brillante. MÉTODOS: Se realizaron mediciones a 60 sujetos (de edades comprendidas entre 18 y 65 años) en un diseño contralateral en el que se asignó aleatoriamente un tipo a cada ojo. Durante la prueba con activación, se realizaron todas las medidas visuales de ambas lentes en estudio, mientras se iluminaba cada ojo con un activador violeta (lambdamáx.=365, ancho de banda medio 20 nm), que causó una activación del estado de equilibrio de las lentes fotocromáticas durante el periodo de prueba. Se determinaron los umbrales de dos puntos, midiendo la distancia mínima entre dos puntos de luz de xenón de banda ancha. Se midió la geometría del reflejo utilizando una apertura (∼ 4 mm) que creó una fuente fija brillante de luz a 45 pulgadas del plano del ojo. Entre la fuente fija y el sujeto se utilizó un calibrador de precisión de centrado para medir la expansión lateral de los halos (difusión alrededor de la fuente) y los destellos. La cabeza se estabilizó utilizando un reposacabezas, alineándose y supervisándose el ojo con una cámara. RESULTADOS: Realizando una comparación con las lentes no fotocromáticas, y sobre la base de las condiciones de estímulo utilizadas en estas medidas, las lentes con activación y desactivación fotocromática redujeron la expansión de la luz utilizando la técnica del umbral de dos puntos en un 32% y un 19% respectivamente; el diámetro de los halos se redujo en un 44% y 16% respectivamente; y los brillos se estrecharon en un 39% y 20% respectivamente. Basándonos en la prueba del intervalo de confianza del 95%, todos estos efectos fueron estadísticamente significativos (p < 0,05). CONCLUSIONES: Estos resultados son consistentes con los datos previos, que reflejan que las lentes de contacto fotocromáticas pueden mejorar muchos aspectos de la función visual, en consistencia con su nivel de activación. Nuestros datos anteriores se centraron en la función visual en condiciones de luz brillante (ej.: incapacidad por deslumbramiento, incomodidad, recuperación de foto-estrés y contraste cromático) con activación de adición fotocromática. En este estudio, encontramos diferencias incluso en el estado de inactivación, utilizando estímulos menos intensos (10 cd/m2 en la fuente), lo cual sugiere que las lentes fotocromáticas mejoran los efectos de la dispersión luminosa incluso con una luminancia menor

The Effect of a Photochromic Contact Lens on Visual Function Indoors: A Randomized, Controlled Trial.

SIGNIFICANCE: Photochromic soft contact lenses contain light-sensitive additives that allow them to darken when exposed to ultraviolet or violet light. One question, however, is whether the lenses influence vision indoors (minimally activated). In this study, we found that the minimally activated lenses improved many aspects of visual function under bright light. PURPOSE: Photochromic contact lenses were designed to darken when exposed to outdoor sunlight. The filtering that results improves visual function under bright light conditions. Not all bright light exposures occur outdoors. In this study, we tested whether a photochromic contact lens improved visual function under conditions where the lens was minimally activated (i.e., no more than it normally would be in an indoor environment). METHODS: A subject-masked contralateral design was used comparing a photochromic contact lens randomized to one eye against a nonphotochromic contact in the other eye of the same subject. Sixty subjects (mean = 34.90 ± 11.24 years) were tested. The primary endpoints consisted of four visual function outcomes: photostress recovery, glare disability, glare discomfort, and chromatic contrast. Photostress recovery was quantified by measuring the time needed to recover visual acquisition of a grating target after 5 seconds of an intense xenon white flash exposure; glare disability was evaluated as the energy in a surrounding xenon white annulus necessary to veil a central grating target; and glare discomfort was assessed using bioimaging of the squint response. Chromatic contrast was measured as thresholds for a green-yellow (580 nm) grating target superposed on a blue (460 nm) background. RESULTS: The minimally activated photochromic contact demonstrated improved visual performance compared with the nonphotochromic control across all visual functions tested (P < .01). CONCLUSIONS: Even under conditions of exiguous activation (e.g., as would be expected indoors or while driving at night), a photochromic contact will improve many of the more deleterious aspects of bright light.

The effects of light scatter when using a photochromic vs. non-photochromic contact lens.

PURPOSE: To assess the visual effects of wearing both an activated and an inactivated photochromic contact lens, with a direct comparison to a non-photochromic contact lens worn in the fellow eye. This study focused on the visual effects of scatter quantified as the minimum distance between two points of light, and the diameter of the halo and starbursts that surround a bright white point source. METHODS: 60 subjects (aged 18-65 years) were measured in a contralateral design where lens type was randomly assigned, one type to each eye. During activated testing, all visual measures of both study lenses were made while each eye was illuminated by a violet (λmax=365, half bandwidth 20nm) activator, which caused steady-state activation of the photochromic lens during the period of testing. Two-point thresholds were determined by measuring the minimum distance between two points of broadband xenon light. Glare geometry was measured using an aperture (∼4mm) that created a bright point source of light 45 inches from the plane of the eye. Between the point source and subject, a centering precision caliper was used to measure lateral spread of halos (diffusion around the source) and visual spokes. The head was stabilized using an adjustable head-rest assembly and the eye was aligned and monitored with a bore camera. RESULTS: Compared to the non-photochromic lens, and based on the stimulus conditions used in these measurements, the activated and inactivated photochromic lens reduced the light spread using the two-point threshold technique by 32% and 19% respectively; the diameter of the halos were reduced by 44% and 16% respectively; and the spokes were narrowed by 39% and 20% respectively. Based on 95% confidence interval testing, these effects were all statistically significant (p<0.05). CONCLUSIONS: These results are consistent with previous data showing that soft contact lenses with a photochromic additive can improve many aspects of visual function, consistent with their level or activation. Our past data focused on visual function under bright light conditions (e.g., glare disability, discomfort, photostress recovery and chromatic contrast) with an activated photochromic. In this study, we found differences even in the inactivated state, using less intense stimuli (10cd/m2 at the source). This suggests that the photochromic lens improves the effects of light scatter even at lower luminance.

The effects of lutein and zeaxanthin on resting state functional connectivity in older Caucasian adults: a randomized controlled trial.

The carotenoids lutein (L) and zeaxanthin (Z) accumulate in retinal regions of the eye and have long been shown to benefit visual health. A growing literature suggests cognitive benefits as well, particularly in older adults. The present randomized controlled trial sought to investigate the effects of L and Z on brain function using resting state functional magnetic resonance imaging (fMRI). It was hypothesized that L and Z supplementation would (1) improve intra-network integrity of default mode network (DMN) and (2) reduce inter-network connectivity between DMN and other resting state networks. 48 community-dwelling older adults (mean age = 72 years) were randomly assigned to receive a daily L (10 mg) and Z (2 mg) supplement or a placebo for 1 year. Resting state fMRI data were acquired at baseline and post-intervention. A dictionary learning and sparse coding computational framework, based on machine learning principles, was used to investigate intervention-related changes in functional connectivity. DMN integrity was evaluated by calculating spatial overlap rate with a well-established DMN template provided in the neuroscience literature. Inter-network connectivity was evaluated via time series correlations between DMN and nine other resting state networks. Contrary to expectation, results indicated that L and Z significantly increased rather than decreased inter-network connectivity (Cohen's d = 0.89). A significant intra-network effect on DMN integrity was not observed. Rather than restoring what has been described in the available literature as a "youth-like" pattern of intrinsic brain activity, L and Z may facilitate the aging brain's capacity for compensation by enhancing integration between networks that tend to be functionally segregated earlier in the lifespan.

The Effects of Lutein and Zeaxanthin Supplementation on Brain Morphology in Older Adults: A Randomized, Controlled Trial.

A growing literature emphasizes the importance of lifestyle factors such as nutrition in successful aging. The current study examined if one year of supplementation with lutein (L) and zeaxanthin (Z), two nutrients with known antioxidative properties and cognitive benefits, impacted structural brain outcomes in older adults using a double-blind, randomized, placebo-controlled trial design. Community-dwelling older adults (20 males and 27 females) aged 65-87 years (M = 71.8 years, SD = 6.04 years) were randomized into supplement (N = 33) and placebo groups (N = 14) using simple randomization. The supplement group received 10 mg L + 2 mg Z daily for 12 months while the placebo group received a visually identical, inert placebo. L and Z were measured via retinal concentrations (macular pigment optical density or MPOD). Structural brain outcomes, focusing on global and frontal-temporal lobe regions, were acquired using both T1-weighted and DTI MRI sequences. We hypothesized that the supplement group would increase, maintain, or show attenuated loss in hypothesized regions-of-interest (ROIs) while the placebo group would show age-related declines in brain structural integrity over the course of the trial. While results showed age-related declines for frontal and temporal gray and white matter volumes, as well as fornix white matter microstructure across both groups, only minimal differences were found between the supplement and placebo groups. However, exploratory analyses showed that individuals who responded better to supplementation (i.e., showed greater increases in MPOD) showed less decline in global and prefrontal gray matter volume than supplement "nonresponders." While results suggest that one year of L and Z supplementation may have limited effects on structural brain outcomes overall, there may be a subsample of individuals for whom supplementation of L and Z provides greater benefits. ClinicalTrials.gov number, NCT02023645.

Dietary Carotenoids Lutein and Zeaxanthin Change Brain Activation in Older Adult Participants: A Randomized, Double-Masked, Placebo-Controlled Trial.

SCOPE: Steady-state visual evoked potentials (SSVEP) can be used to test the topological response of cortical neurons. Studies have shown that a lutein (L) preferentially accumulates within cortical tissue. L, zeaxanthin (Z), and their isomers can be measured directly in retina (macular pigment optical density, MPOD), and retinal L+Z correlate highly with L+Z levels in cortical visual processing areas. The purpose of this study was to determine the relation between MPOD and SSVEP signal power, cross-sectionally and after supplementation with L+Z. METHODS AND RESULTS: SSVEP to three different driving frequencies of stimulation (5, 10, and 16.6 Hz) were obtained for community-dwelling older adults, at baseline and after 12 months of supplementation with either 12 mg L+Z or placebo. Power was quantified at the driving frequencies. Non-specific activation was quantified within the 10-15 Hz band. MPOD was measured psychophysically. Subjects with low MPOD had reduced power at 16.6 Hz and reduced non-specific activation, compared with subjects with high MPOD. Supplementation significantly improved signal power at 5 and 10 Hz. CONCLUSION: Past research suggests that L+Z can improve visual memory, visual processing speeds, etc. One possible mechanism for that improvement may be improving signal-to-noise ratio throughout the vision system.

Neural Activation During Visual Attention Differs in Individuals with High versus Low Macular Pigment Density.

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.

Intelligence moderates the relationship between age and inter-connectivity of resting state networks in older adults.

Age-related changes in the interactive behavior of default mode network (DMN) with other resting state networks are poorly understood. We hypothesized that age would positively correlate with inter-network connectivity in late life and intellectual functioning was expected to moderate this relationship. The sample consisted of 48 community-dwelling older adults with resting state functional magnetic resonance imaging data. Global inter-connectivity between DMN and 9 other resting state networks was calculated using a novel computational framework based on machine learning. Intellectual functioning (intelligence) was estimated using the Wechsler Test of Adult Reading. A significant, positive relationship was found between age and global inter-network connectivity (r = 0.31, p = 0.029). Moderation analyses yielded a significant age × intelligence interaction term (p = 0.003), such that intelligence attenuated the relationship between age and global inter-network connectivity. Taken together, these results suggest that age is positively associated with global DMN desegregation, possibly due to dedifferentiation or compensation. Intellectual functioning moderates this relationship, such that more intelligent older adults maintain a segregated DMN profile.

Lutein and Zeaxanthin Are Positively Associated with Visual-Spatial Functioning in Older Adults: An fMRI Study.

Lutein (L) and zeaxanthin (Z) are two xanthophyll carotenoids that have antioxidant and anti-inflammatory properties. Previous work has demonstrated their importance for eye health and preventing diseases such as age-related macular degeneration. An emerging literature base has also demonstrated the importance of L and Z in cognition, neural structure, and neural efficiency. The present study aimed to better understand the mechanisms by which L and Z relate to cognition, in particular, visual-spatial processing and decision-making in older adults. We hypothesized that markers of higher levels of L and Z would be associated with better neural efficiency during a visual-spatial processing task. L and Z were assessed via standard measurement of blood serum and retinal concentrations. Visual-spatial processing and decision-making were assessed via a judgment of line orientation task (JLO) completed during a functional magnetic resonance imaging (fMRI) scan. The results demonstrated that individuals with higher concentrations of L and Z showed a decreased blood-oxygen-level dependent (BOLD) signal during task performance (i.e., "neural efficiency") in key areas associated with visual-spatial perception, processing, decision-making, and motor coordination, including the lateral occipital cortex, occipital pole, superior and middle temporal gyri, superior parietal lobule, superior and middle frontal gyri, and pre- and post-central gyri. To our knowledge, this is the first investigation of the relationship of L and Z to visual-spatial processing at a neural level using in vivo methodology. Our findings suggest that L and Z may impact brain health and cognition in older adults by enhancing neurobiological efficiency in a variety of regions that support visual perception and decision-making.

The Macular Carotenoids are Associated with Cognitive Function in Preadolescent Children.

The macular carotenoids lutein (L) and zeaxanthin (Z) are obtained via diet and accumulate in the central retina where they are referred to as macular pigment. The density of this biomarker (macular pigment optical density; MPOD) has been positively correlated with cognitive functioning via measures of global cognition, processing speed, and visual-spatial abilities, among others. Although improvements in cognitive function have been found in adults, much less is known about how L and Z intake may support or improve cognitive functioning during periods of rapid developmental change, such as childhood and pre-adolescence. This study examined the relationship between MPOD and cognitive functioning in 51 7-13-year-old children (51% female). MPOD was measured using heterochromatic flicker photometry (HFP) optimized for this age group. Cognitive function was assessed using the Woodcock-Johnson III (composite standard scores were obtained for Brief Intellectual Ability, Verbal Ability, Cognitive Efficiency, Processing Speed, and Executive Processes). In this sample, MPOD was significantly related to Executive Processes, r(47) = 0.288, p < 0.05, and Brief Intellectual Ability, r(47) = 0.268, p < 0.05. The relationship to Cognitive Efficiency was positive and trending but not significant, r(49) = 0.206, p = 0.074. In general, these data are consistent with those of adults showing a link between higher carotenoid status and improved cognitive functioning.