scholarly journals ON SENSITIVITY TO GLARE AND ITS RELATIONSHIP WITH MACULAR PIGMENT

2021 ◽  
Author(s):  
Sneha Jain ◽  
Jan Wienold ◽  
Marilyne Andersen

Current trends in discomfort glare research have suggested the influence of physiological parameters on individual glare perception. To this end, we hypothesize that a specific ocular physiology characteristic, namely the macular pigment (MP) in the retina, could have an influence on glare sensitivity, encouraged by recent findings from the literature that have shown that high MP levels were indicative of better visual performance. This study investigates whether a person’s sensitivity to glare could be somehow correlated to their macular pigment optical density (MPOD). We measured MPOD in 56 participants and compared it with their discomfort glare thresholds, which were determined psychophysically by exposing the participants to a series of lighting conditions varying in intensity. We found that the influence of MPOD on glare sensitivity is borderline significant with small effect size but does not follow intuition. Additional data will be required to validate and refine these initial findings.

2019 ◽  
Vol 52 (2) ◽  
pp. 167-188 ◽  
Author(s):  
C Jarboe ◽  
J Snyder ◽  
MG Figueiro

Architectural lighting has traditionally addressed visual performance and horizontal illuminance on the work plane, later focussing on energy efficiency, while only recently paying particular regard to human health outcomes. The present study evaluated the effectiveness of several light-emitting diode lighting strategies for delivering circadian stimulus to occupants of a typical office space while minimizing energy use. The study employed photometric simulations in a typical open-office space, delivering a criterion circadian stimulus of 0.3 to calculation points modelled at the simulated occupants’ eye level. Six luminaire types, two luminous intensity distributions, six spectral power distributions and two horizontal illuminances were evaluated, resulting in 144 unique lighting conditions. Additionally, the study calculated the discomfort glare for selected luminaires with the highest total lumen output, smallest aperture and direct-only luminous intensity distributions at the higher of the two horizontal illuminances (500 lx). The most impactful strategy involved supplementing common overhead lighting with a desktop luminaire delivering light directly to the simulated office occupants’ eyes, which provided greater circadian stimulus and used less energy than overhead luminaires that were capable of delivering the criterion circadian stimulus of 0.3.


Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2966
Author(s):  
Naomichi Machida ◽  
Marie Kosehira ◽  
Nobuyoshi Kitaichi

Improvements in macular pigment optical density (MPOD) and contrast sensitivity after administration of 12 mg lutein alone and the timing at which efficacy is observed remain unknown. Therefore, lutein (12 mg), a crystalline formulation, was used in this study, considering its bioaccessibility. This study aimed to determine the effects of lutein administration for 16 weeks on MPOD, contrast sensitivity, and glare sensitivity, and changes in serum lutein levels were determined. The study subjects comprised 59 healthy male and female adults aged 20–69 years. The study diet included a placebo (placebo group) or a diet supplemented with 12 mg of lutein (lutein group). Each study diet was continuously administered for 16 weeks. At weeks 8 and 16, MPOD, contrast sensitivity, glare sensitivity, and serum lutein levels were evaluated. Compared with the placebo group, the lutein group showed significantly improved MPOD, contrast sensitivity, and glare sensitivity at week 16 and significantly increased serum lutein levels at weeks 8 and 16. Continuous administration of lutein for 16 weeks, considering its bioaccessibility, increased MPOD; it made the outlines of visible objects clearer and was effective in inhibiting decreases in visual function caused by glare from light.


2016 ◽  
Vol 16 (4) ◽  
pp. 197-200
Author(s):  
E.N. Eskina ◽  
◽  
E.A. Egorov ◽  
A.V. Belogurova ◽  
А.А. Gvetadze ◽  
...  

Author(s):  
Hadi Nobari ◽  
Sara Mahmoudzadeh Khalili ◽  
Rafael Oliveira ◽  
Alfonso Castillo-Rodríguez ◽  
Jorge Pérez-Gómez ◽  
...  

Soccer is a popular team sport and highly demanding activity that requires high effort and long-term training plans. The goals of this study were to compare the accelerations, decelerations and metabolic power between official and friendly full matches, between the first and second halves of the matches, and between both halves of official and friendly matches. Twelve professional soccer players (age, 28.6 ± 2.7 years; height, 182.1 ± 8.6 cm; body mass, 75.3 ± 8.2 kg; BMI, 22.6 ± 0.7 kg/m2) participated in this study. A total of 33 official and 10 friendly matches were analyzed from the Iranian Premier League. All matches were monitored using GPSPORTS systems Pty Ltd. The following variables were selected: total duration of the matches, metabolic power, accelerations Zone1 (<2 m·s−2) (AccZ1), accelerations Zone2 (2 to 4 m·s−2) (AccZ2), accelerations Zone3 (>4 m·s−2) (AccZ3), decelerations Zone1 (<−2 m·s−2) (DecZ1), decelerations Zone2 (−2 to −4 m·s−2) (DecZ2) and decelerations Zone3 (>−4 m·s−2) (DecZ3). The major finding was shown in metabolic power, where higher values occurred in friendly matches (p < 0.05 with small effect size). Furthermore, total duration, AccZ3, DecZ1, DecZ2, and DecZ3 were revealed to be higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches. The second half of the official matches revealed higher values for total duration compared to friendly matches (p < 0.05, moderate effect size). In conclusion, this study observed higher values of metabolic power in friendly matches compared to official matches. AccZ3, DecZ1, DecZ2, and DecZ3 were higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Catherine V. Barnes-Scheufler ◽  
Caroline Passow ◽  
Lara Rösler ◽  
Jutta S. Mayer ◽  
Viola Oertel ◽  
...  

Abstract Background Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies. However, it has not yet been investigated across the full spectrum of both disorders. The aim of our study was to compare the degree of reductions of visual working memory capacity in patients with bipolar disorder (PBD) and patients with schizophrenia (PSZ) using a paradigm well established in cognitive neuroscience. Methods 62 PBD, 64 PSZ, and 70 healthy controls (HC) completed a canonical visual change detection task. Participants had to encode the color of four circles and indicate after a short delay whether the color of one of the circles had changed or not. We estimated working memory capacity using Pashler’s K. Results Working memory capacity was significantly reduced in both PBD and PSZ compared to HC. We observed a small effect size (r = .202) for the difference between HC and PBD and a medium effect size (r = .370) for the difference between HC and PSZ. Working memory capacity in PSZ was also significantly reduced compared to PBD with a small effect size (r = .201). Thus, PBD showed an intermediate level of impairment. Conclusions These findings provide evidence for a gradient of reduced working memory capacity in bipolar disorder and schizophrenia, with PSZ showing the strongest degree of impairment. This underscores the importance of disturbed information processing for both bipolar disorder and schizophrenia. Our results are compatible with the cognitive manifestation of a neurodevelopmental gradient affecting bipolar disorder to a lesser degree than schizophrenia. They also highlight the relevance of visual working memory capacity for the development of both behavior- and brain-based transdiagnostic biomarkers.


2020 ◽  
Vol 9 (5) ◽  
pp. 1347 ◽  
Author(s):  
Norihiro Nagai ◽  
Sakiko Minami ◽  
Misa Suzuki ◽  
Hajime Shinoda ◽  
Toshihide Kurihara ◽  
...  

To explore predisease biomarkers, which may help screen for the risk of age-related macular degeneration (AMD) at very early stages, macular pigment optical density (MPOD) and photoreceptor outer segment (PROS) length were analyzed. Thirty late AMD fellow eyes, which are at high risk and represent the predisease condition of AMD, were evaluated and compared with 30 age-matched control eyes without retinal diseases; there was no early AMD involvement in the AMD fellow eyes. MPOD was measured using MPS2® (M.E. Technica Co. Ltd., Tokyo, Japan), and PROS length was measured based on optical coherence tomography images. MPOD levels and PROS length in the AMD fellow eyes were significantly lower and shorter, respectively, than in control eyes. MPOD and PROS length were positively correlated in control eyes (R = 0.386; p = 0.035) but not in AMD fellow eyes. Twenty (67%) AMD fellow eyes met the criteria of MPOD < 0.65 and/or PROS length < 35 μm, while only five (17%) control eyes did. After adjusting for age and sex, AMD fellow eyes more frequently satisfied the definition (p < 0.001; 95% confidence interval, 3.50–60.4; odds ratio, 14.6). The combination of MPOD and PROS length may be a useful biomarker for screening predisease AMD patients, although further studies are required in this regard.


2021 ◽  
Vol 13 ◽  
pp. 251584142199719
Author(s):  
Burcu Polat Gultekin ◽  
Esra Sahli

Purpose: The aim of our study was to evaluate the macular pigment optical density in patients with acute and chronic central serous chorioretinopathy and to describe the association between central retinal thickness and choroidal thickness with the macular pigment optical density. Materials and Methods: Eyes with acute central serous chorioretinopathy and chronic central serous chorioretinopathy (patients, who were diagnosed as having disease activity for 6 months) were included in this study. Macular pigment was measured using the heterochromatic flicker technique of the MPS II device for both eyes in patients with acute and chronic central serous chorioretinopathy and in control subjects. Results: Twenty-seven eyes with acute central serous chorioretinopathy, 23 eyes with chronic central serous chorioretinopathy, and 25 control eyes were enrolled. The mean macular pigment optical density in chronic central serous chorioretinopathy (0.480 ± 0.16 density unit (95% confidence interval: 0.390–0.570) was found to be significantly lower than in the control eyes (0.571 ± 0.128 density unit) (95% confidence interval: 0.480–0.670) ( p = 0.007). In correlation analysis, no significant association was detected between the central retinal thickness, choroidal thickness, and macular pigment optical density values in central serous chorioretinopathy group ( p = 0.31, p = 0.71). Conclusion: Macular pigment optical density levels were significantly lower in chronic central serous chorioretinopathy patients than in controls, possibly due to degeneration of the neurosensorial retina, as a result of the long-term persistence of subretinal fluid. There was not a significant correlation between choroidal thickness and macular pigment optical density levels in central serous chorioretinopathy group.


2013 ◽  
Vol 251 (12) ◽  
pp. 2831-2832
Author(s):  
Lin Miao ◽  
Zhen-Yong Zhang ◽  
Zhi-Qiang Yu ◽  
Chong-Da Chen

2021 ◽  
Author(s):  
Bastien Trémolière ◽  
Corentin J Gosling

Recent research has shown mixed evidence for the morning morality effect (i.e., the observation that individuals are less immoral in the morning than in the afternoon). In the present research, we target the morning morality effect in the context of moral utilitarianism, by reanalyzing observational data previously collected by our lab. These data include different tasks capturing moral utilitarianism (i.e., standard sacrificial dilemmas, an ecological utilitarian scale, and/or dilemmas involving the morality of autonomous vehicles). We report a meta-analysis of 6 studies which showed that participants became less utilitarian as the day goes on, but with a small effect size (r = -0.14) and a large heterogeneity. Exploration of this heterogeneity showed that such a conclusion was statistically significant for classic sacrificial dilemmas only. Notably, even when restricting the analysis to the classic sacrificial dilemmas, a moderate inconsistency remained. Post-hoc analysis of an individual study showed that this small effect did not survive the inclusion of potentially confounding variables, such as psychopathy trait and cognitive reflection. Implications and limitations are discussed.


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