Red-green Color Vision Research Articles

Arabic Reading Performance With a Chromatic Acuity Chart.

This study compared the reading performance for Arabic text defined by chromatic and achromatic contrast to understand better how chromatic contrast affects reading of normally sighted individuals and to establish a baseline for determining whether patients have a selective red-green chromatic sensitivity loss. Reading performance for Arabic text was accessed by examining maximum reading speed (MRS), reading acuity (RA), critical print size (CPS), and the Reading Accessibility Index (ACC) using three near-point charts. The charts were the black-on-white Balsam Alabdulkader-Leat (BAL) chart, a red-on-green chart, and a gray-on-gray chart with a background luminance equal to the chromatic chart. The MRSs were significantly different (P = 0.03), with the red-on-green chart having a slightly higher value than the BAL chart. The ACC was lower for the BAL chart than the red-on-green and gray charts (P = 0.003). However, RA for the BAL chart was better, and the CPS was smaller relative to the red-on-green chart (P < 0.05) and gray chart (P < 0.001). Individuals with red-green color vision deficiencies had poorer RA and larger CPS on the red-on-green chart relative to the achromatic charts. Although the MRS and ACC of the chromatic chart were significantly higher, the difference was not clinically important. The result that the MRS was similar for all three charts confirmed earlier findings that MRS is similar if text contrast is sufficiently above threshold. The lower RA and corresponding larger CPS for the red-on-green and gray charts were due to their lower background luminance and lower contrast.

From a color-blind perspective: exploring frustration and confidence in schoolchildren with simulated color vision deficiency

Congenital red–green color vision deficiencies (CVDs) affect 8% of males and 0.5% of females. Given the growing number of school materials using color as a resource to learn, affected children are said to be at a clear disadvantage. However, due to an absence of mandatory screening, CVD goes unnoticed in the majority of children with the condition, and necessary adjustments are not made, raising questions about the potential impact on their future motivation to learn. The aim of the current study was to examine children’s levels of frustration and self-confidence after inducing CVD. Commercially available Variantor spectacles (simulating dichromacy, affecting 2% of males) were worn by the children while they performed a typical color-based task at school. Using a counterbalanced, repeated measures design, the study was conducted on 181 color-normal schoolchildren performing age-appropriate math tasks. Wilcoxon signed-rank tests revealed significantly poorer task performance, higher levels of frustration, and lower confidence ratings in the simulation condition. We argue that frequent failure at color-related tasks can lead to academic and social–emotional problems, highlighting the need to reintroduce CVD screening at an early age to ensure that appropriate support can be given to CVD children at school.

Impact of EnChroma glasses on red-green color vision deficiency: a prospective study.

Impact of EnChroma glasses on red-green color vision deficiency: a prospective study.

Evaluation of SeeColors filters for color vision correction and comparative analysis with EnChroma glasses

Evaluation of SeeColors filters for color vision correction and comparative analysis with EnChroma glasses

Evaluation of contrast sensitivity in patients with congenital red-green color vision deficiency.

To evaluate mesopic and photopic contrast sensitivity in patients with congenital red-green color vision deficiency regarding with and without glare conditions and to compare these findings with age- and gender-matched healthy controls with normal color vision. Patients with congenital red-green color vision deficiency and age- and gender-matched healthy controls were included in this cross-sectional comparative study. Contrast sensitivity measurements were taken from all subjects in 4 different conditions; binocular mesopic-without glare, mesopic-with glare, photopic-without glare, photopic-with glare, and the results were compared. Twenty one patients with color vision deficiency (13 deuteranopic, 8 protanopic) and 22 age- and gender-matched healthy controls were included in the study. The mean age was 35.2 ± 13.5years in the protan group, 30.6 ± 7.7years in the deutan group, 32.0 ± 8.8years in the control group, and there was no significant difference in age between the groups (P > 0.05). The mean mesopic and photopic contrast sensitivity values of the groups at all spatial frequencies (1.5, 3, 6, 12, 18cpd) were not statistically significant when evaluated by the multifactor repeated measures test of ANOVA to evaluate the effect of light conditions (with and without glare) (P > .05). Mesopic and photopic contrast sensitivity values of patients with congenital red-green color vision deficiency were similar to healthy controls regarding with and without glare conditions.

The Impact of Colour Vision Defect on Consumer’s Fruits Selection Process while Purchasing from Retail Fruit Shops in Bangladesh

Color Vision Defect affects about one in twelve males and two hundred women worldwide, according to research. CVD has a big impact in almost every marketing and branding circumstance, especially when product color is the key. This study began with a Red-Green CVD test of 522 Dhaka residents. Since few research have measured color blindness in Bangladesh, this study can be used as one of the Bangladesh color vision deficiency baseline results. The important factor of this study is whether this result is comparable to Bangladesh’s earlier result and whether Bangladesh has a lower/higher CVD prevalence than other nations. The most common CVD is Red-Green Colour Vision Defect. Green fruits turn yellow and red when maturing and CVD patients have trouble distinguishing neighboring colours like Red, Green, Brown, etc. After examining baskets of green and ripe yellow, red, and partly reddish fruits, this study evaluated the findings. This study found out that people with color vision defects had trouble choosing fruits from baskets. Furthermore, the study tested hypotheses to determine severity of Red-Green CVD and found out it to be less than expected probably due to coping mechanism, experience etc. in Red-Green CVD subjects.

Ocular toxicity of daily anti-tubercular treatment regimen: A prospective observational study

Context: India carries a significant burden of TB which is the commonest cause of infectious disease-related mortality. Anti-tubercular drugs can cause serious ocular toxic effects. Optical coherence tomography (OCT) can be used as a valuable tool in the quantitative analysis of anti-tubercular treatment (ATT)-induced toxic optic neuropathy. Aims: To study the changes in visual parameters in patients on ATT and to analyze the OCT changes in patients by taking measurements once before initiation of treatment and once during ongoing treatment (between three and six months). Settings and Design: Tertiary care center, Prospective observational study. Methods and Material: A prospective observational study was conducted in 140 eyes of 70 subjects undergoing ATT as per the latest RNTCP guidelines where the following determinants were examined, and the corresponding values were taken once before initiation of treatment and once during ongoing treatment (between three and six months) and results were analyzed. Around 90% of the subjects were examined at the end fourth month. Visual acuity was taken using the Log Mar chart, color vision using Ishihara’s chart, and slit lamp examination and fundus evaluation using a 90 D lens. OCT was done and average nasal, temporal, superior, and inferior quadrant retinal nerve fiber layer (RNFL) measurements were taken. Perimetry was also done; however, findings were not included in this study. Statistical Analysis Used: Frequency and percentage were applied to study the changes in visual parameters in patients on ATT. A paired t-test was applied for numerical variables to analyze the OCT changes in patients undergoing ATT. A P value &lt; 0.05 was considered statistically significant. Results: Despite a near-normal appearance of the fundus on ophthalmoscopy, OCT clearly demonstrated and quantified the loss of retinal nerve fibers. Statistically significant RNFL thinning (P value &lt; 0.001) was noted in the superior, temporal, and inferior quadrants and least in the nasal quadrant (P = 0.005). Significant deterioration in visual acuity was observed following three months of ATT (P = 0.001). Red-green color vision abnormalities were detected in 14 out of 140 eyes (10%). Conclusions: RNFL thickness was reduced on OCT. RNFL thickness quantification and assessment of other visual parameters especially color vision help in the early diagnosis of ocular toxic effects of ATT. Hence, awareness and active screening are imperative in preventing visual impairment and blindness.

Evaluation of the Efficacy of Enchroma Filters for Correcting Color Vision Impairment

Objective: This study examined the effectiveness of Enchroma Cx-14 filters on individuals with Red-Green color vision deficiency (CVD). Methods: ColorDx and the Farnsworth-Munsell (FM) 100-Hue test were used to assess subjective reactions to Enchroma. The ColorDx and FM, 100 Hue test error scores were computed and contrasted using Placebo (untinted glasses) and Enchroma CX-14, red, and green filters. Results: The findings demonstrated that while enchroma filters improved the mistake score in only two patients, they had no discernible impact on any CVD subject's performance. In one protan participant and all deutan individuals, colour discrimination was greatly enhanced by the red filter. Green filters and Enchroma did not raise mean error scores. Conclusion: Enchroma filters had limited effectiveness in improving color perception for individuals with Red-Green CVD.

Validation of a New Digital and Automated Color Perception Test.

Although color vision deficiencies are very prevalent, there are no ideal methods for assessing color vision in all environments. We compared a new digital and automated method that quantifies color perception for the three protan, deutan, and tritan axes with two of the most commonly used color tests in daily practice: the Ishihara 38 plates test and the Farnsworth-Munsell 100-Hue test. One hundred patients underwent a triple examination composed of the new DIVE Color Test, the Ishihara test, and the Farnsworth-Munsell 100-Hue test. The DIVE Color Test was performed twice in forty participants to assess its repeatability. In the trichromatic group, the mean age stood at 20.57 ± 9.22 years compared with 25.99 ± 15.86 years in the dyschromatic group. The DIVE and Ishihara tests exhibited excellent agreement in identifying participants with color deficiency (Cohen's kappa = 1.00), while it was 0.81 when comparing DIVE and Farnsworth. The correlation between the global perception values of Farnsworth (TES) and DIVE (GCS) was 0.80. The repeatability of the DIVE Color Test was high according to Bland-Altman analysis with an intraclass correlation coefficient of 0.83. According to Ishihara, the DIVE Color Test proved to be an effective and reproducible tool for red-green color vision deficiency detection, capable of determining the severity of the defect in each of the three axes faster and more accurately than both Ishihara and Farnsworth.

Comparison of Two Printed Pseudoisochromatic Tests for Color Vision Assessment.

The Waggoner PIP24 is a pseudoisochromatic test with a pattern similar to the Ishihara test. This study determined that the W-PIP24 can be used clinically to yield screening results (or sensitivity and specificity) comparable with the Ishihara. This study aimed to determine whether the W-PIP24 is equivalent to the Ishihara 38 edition pseudoisochromatic test in detecting red-green color vision defects. Also, the performance of each plate of the W-PIP24 in detecting the color vision defects relative to the Ishihara test was determined. Sixty-three individuals with congenital red-green color vision defects and 57 with normal trichromacy were recruited. Participants were tested with both the Ishihara and W-PIP24. The first-order agreement coefficients were calculated for the Ishihara and W-PIP24. The results were also analyzed using specificity, sensitivity, efficiency, and predictive pass and fail values. The agreement between the W-PIP24 and Ishihara test using the recommended criterion of using all plates was perfect. The sensitivity, specificity, predictive pass, and predictive fail were 1.00 (95% confidence interval, 0.94 to 1.00). This study showed that the W-PIP24 using a failure criterion of three or more errors on screening plates 1 to 15 is equivalent to the Ishihara test while screening for red-green color vision deficiency using a failure criterion of three or more errors on screening plates 1 to 17 of the Ishihara 38 edition.

The prevalence of red-green color vision deficiency and its related factors in an elderly population above 60 years of age.

To determine the prevalence of red-green (RG) color vision deficiency (CVD) in an elderly population and its related factors. This report is a part of the Tehran Geriatric Eye Study: a cross-sectional population-based study that was conducted on the elderly population (≥60y) of Tehran, Iran using multi-stage stratified random cluster sampling. All study participants underwent complete ocular examination, including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, and slit-lamp biomicroscopy. The color vision was tested using Ishihara plates with the near optical correction in place. Of the 3791 invitees, 3310 participated in the study. The data of 2164 individuals were analyzed after applying the exclusion criteria. The prevalence of R-G CVD was 3.73% (95%CI: 2.37%-5.09%) in the whole sample; the prevalence of protanomaly, protanopia, and deuteranopia was 1.51%, 1.76%, and 0.45%, respectively. The prevalence of R-G CVD was significantly higher in males than in females. The prevalence of RG CVD increased with advancing age from 2.91% in the age group 60-64y to 5.8% in the age group ≥80y (P=0.070). According to the multiple logistic regression model, male sex, and glaucoma were significantly related to RG CVD. Older age and hypertension also had a marginally significant relationship with RG CVD. Changes in color vision occur in the elderly due to the aging process and some physiological and pathological factors. Since the change in visual perception may affect the person's performance, this aspect of the visual system's function should also be taken into consideration in the examinations of the elderly.

Little information loss with red-green color deficient vision in natural environments

Inherited color vision deficiency affects red-green discrimination in about one in twelve men from European populations. Its effects have been studied mainly in primitive foraging but also in detecting blushing and breaking camouflage. Yet there is no obvious relationship between these specific tasks and vision in the real world. The aim here was to quantify the impact of color vision deficiency by estimating computationally the information available to observers about colored surfaces in natural scenes. With representative independent sets of 50 and 100 hyperspectral images, estimated information was found to be only a little less in red-green color vision deficiency than in normal trichromacy. Colorimetric analyses revealed the importance of large lightness variations within scenes, small redness-greenness variations, and uneven frequencies of different colored surfaces. While red-green color vision deficiency poses challenges in some tasks, it has much less effect on gaining information from natural environments.

BRIDGING DESIGNER-USER GAP WITH A VIRTUAL REALITY-BASED EMPATHIC DESIGN APPROACH: CONTEXTUAL INFORMATION DETAILS

AbstractWithout shared experiences, empathy gaps between designers and users are difficult to bridge. Advancing Virtual Reality (VR) has shed new light on this regard by enabling designers to simulate and experience their users' living scenarios in a virtual environment (VE). However, implementing VR-based empathetic design approach requires dealing with critical design questions, such as: (1) whether VR operators can develop empathy for unfamiliar user groups solely based on objective experience and (2) whether VR operators can utilize task-irrelevant contextual information in the VEs. To explore these issues, we designed an experiment based on two VEs with varying levels of detail that simulated the scenes viewed by people with red-green color vision deficiency (CVD). Participants were randomly assigned to either detail-rich or detail-simple VEs to complete neutral item-searching tasks. Results indicate that objective and neutral experience alone cannot elicit empathy towards users, and VR operating designers will utilize task-irrelevant contextual information.

Clinical analysis of the Konan-Waggoner D15 color vision test using the Surface-Pro display.

This work expands on our previous comparison of the Konan-Waggoner D15 (KW-D15) and Farnsworth D15 (F-D15). Sixty subjects with normal color vision and 68 subjects with a red-green color vision defect participated in the study. The KW-D15 had good agreement with the F-D15 for both pass/fail and classification across all failure criteria. The agreement was slightly better if subjects had to pass on 2/3 trials compared with just the first trial. The KW-D15 is an adequate substitute for the F-D15, with the caveat that the KW-D15 might be slightly easier to pass than the F-D15 for deutans.

A Comparison Between Three Computer-Based Cone Specific Color Vision Tests.

INTRODUCTION: Computerized color contrast sensitivity (CS) tests that aim to determine presence, type, and severity of color vision deficiency have been developed and are available, but data on agreement between tests is lacking. The purpose of the present study was to determine data agreement between three computerized color vision tests.METHODS: A total of 50 subjects, 25 color vision normal (CVN) and 25 color vision deficient (CVD), were tested with the Konan CCT-HD®, NCI, and a modified version of the Innova CCT. Sensitivity and specificity were compared across systems as well as differences in log CS values and how these relate to standards used to classify occupational performance.RESULTS: Each test showed 100% sensitivity for detection of hereditary red-green CVDs as well as type (protan vs. deutan). Each test showed 100% specificity for confirming normal red-green color vision in CVNs. Innova CCT and NCI showed 100% specificity in CVNs and CVDs for S cone CS. Konan CCT-HD® showed 96% specificity in CVNs and 92% in CVDs for S cone CS.DISCUSSION: These findings indicate that each test reliably identifies hereditary CVD and confirms normal color vision. However, the three tests differ slightly in log CS values used to determine pass/fail scores of red-green color vision using a 100-point scale, and all show that protans consistently score lower than deutans on cone CS. Hence, depending on the criterion used in occupational settings, a single score may not prove equitable for individuals who have a protan deficiency.Lovell J, Rabin J. A comparison between three computer-based cone specific color vision tests. Aerosp Med Hum Perform. 2023; 94(2):54-58.

The Verriest Lecture: Pathways to color in the eye and brain.

In common with the majority of New World monkeys, marmosets show polymorphic color vision by allelic variation of X-chromosome genes encoding opsin pigments in the medium/long wavelength range. Male marmosets are thus obligate dichromats ("red-green color blind"), whereas females carrying distinct alleles on X chromosomes show one of three trichromatic phenotypes. Marmosets thus represent a "natural knock-out" system enabling comparison of red-green color vision in dichromatic and trichromatic visual systems. Further, study of short-wave (blue) cone pathways in marmosets has provided insights into primitive visual pathways for depth perception and attention. These investigations represent a parallel line to clinical research on color vision defects that was pioneered in studies by Guy Verreist, whom we honor in this eponymous lecture.

Case report: Prolonged amelioration of mild red-green color vision deficiency following psilocybin mushroom use

Background Recent survey data indicate that some people report long-term improvement in color vision deficiency (CVD), also known as color blindness, following use of psychedelics such as lysergic acid diethylamide (LSD) and psilocybin. However, there are no objective data reported in the medical literature quantifying the degree or duration of CVD improvement associated with psychedelic use. Case presentation Here we present the case of a subject with red-green CVD (mild deuteranomalia) who self-administered the Ishihara Test to quantify the degree and duration of CVD improvement following the use of 5 g of dried psilocybin mushrooms. Self-reported Ishihara Test data from the subject revealed partial improvement in CVD peaking at 8 days and persisting for at least 16 days post-psilocybin administration. This improvement may have lasted longer, though the subsequent observations are confounded by additional substance use. Conclusion A single use of psilocybin may produce partial improvements in CVD extending beyond the period of acute effect, despite this condition typically resulting from a genetic defect. Systematic exploration of this possible phenomenon is needed to confirm our findings, gauge their generalizability, and determine the mechanism of action.

Aids for color vision deficiency: introduction to the feature issue.

Approximately 8% of Caucasian males and 0.5% of females have congenital red-green color vision deficiencies (CVD), and a number of eye diseases are accompanied by acquired CVD. This feature issue includes ten contributions regarding existing and proposed algorithms and devices intended to help CVD subjects compensate for their color deficiencies. It also addresses limitations in the effectiveness of CVD aids for subjects with different types and degrees of color vision deficiency.

Color Vision Deficiency Survey in Anatomic Pathology.

To learn what color vision-deficient pathologists and cytotechnologists consider their most significant problems and advantages as well as any accommodations. An anonymous online survey developed for practicing pathologists and cytotechnologists regarding their experiences with stains was sent to the members of 4 national societies. We received 377 responses. Twenty-three people, all men, identified themselves as color vision deficient, with 22 reporting red-green color vision deficiency and 1 reporting uncertain type. Eight pathologists and cytotechnologists indicated that they thought that their color vision deficiency conferred advantages to them, including a greater appreciation of morphology, with less confusion resulting from variations in stain quality or intensity. Nineteen pathologists and cytotechnologists thought that their color vision deficiency conferred disadvantages; the most common disadvantages stated were the identification of eosinophils and acid-fast bacilli. Other difficulties included interpretation of RBCs and nucleoli and sometimes Alcian blue, Brown and Brenn, Congo red, crystal violet, Fite, Giemsa, mucicarmine, periodic acid-Schiff, and fluorescence in situ hybridization stains. Only 2 of the color vision-deficient pathologists and cytotechnologists found digital slides more difficult than glass slides. Color vision-deficient pathologists and cytotechnologists report that they have developed approaches to viewing slides that do not compromise their interpretations. Digital pathology may provide several approaches for aiding color vision-deficient pathologists with the interpretation of certain stains.

A model for assessing the efficacy of colour vision aids.

Optical filter aids are marketed which claim to improve colour discrimination in red-green colour vision defectives. An earlier model has been revised and used to assess 9 currently available aids. Spectral reflectances (400-700 nm) for 80 colours equally spaced in hue angle at four equally spaced saturations were synthesised from chromatically adjacent Munsell colours. Aid induced chromaticity changes for Protanomals and Deuteranomals were calculated. Five aids enhanced red-green discrimination significantly for Protanomals and six for Deuteranomals and one aid reduced it significantly for both defectives. Five aids enhanced blue-yellow discrimination in Protanomals and Deuteranomals for whom it is not needed.