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1.
Front Neurol ; 15: 1363167, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660098

RESUMEN

Introduction: Traumatic brain injury (TBI) is an important public health concern and that may lead to severe neural sequels, such as color vision deficits. Methods: We evaluated the color vision of 10 TBI patients with normal cognitive function using a color discrimination test in a fixed saturation level. We also analyzed computerized tomography scans to identify the local of the brain damages. Results: Four TBI patients that had lesions in brain areas of the ventral visual streams, five TBI patients had lesions inferred in brain areas of the dorsal visual stream, and one TBI patient had lesion in the occipital area. All the patients had cognitive and color vision screened and they had characterized the chromatic discrimination at high and low saturation. All participants had no significant cognitive impairment in the moment of the color vision test. Additionally, they had perfect performance for discrimination of chromatic stimulus at high saturation and similar to controls (n = 37 age-matched participants). Three of four TBI patients with lesions in the ventral brain and one patient with lesion in the occipital area had impairment of the chromatic discrimination at low saturation. All TBI patients with lesions in the dorsal brain had performance similar or slightly worse than the controls. Conclusion: Chromatic discrimination at low saturation was associated to visual damage in the ventral region of the brain and is a potential tool for functional evaluation of brain damage in TBI patients.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37268825

RESUMEN

Recent research has proposed new approaches to investigate color vision in Old World Monkeys by measuring suprathreshold chromatic discrimination. In this study, we aimed to extend this approach to New World Monkeys with different color vision genotypes by examining their performance in chromatic discrimination tasks along different fixed chromatic saturation axes. Four tufted capuchin monkeys were included in the study, and their color vision genotypes were one classical protanope, one classical deuteranope, one non-classical protanope, and a normal trichromat. During the experiments, the monkeys were required to perform a chromatic discrimination task using pseudoisochromatic stimuli with varying target saturations of 0.06, 0.04, 0.03, and 0.02 u'v' units. The number of errors made by the monkeys along different chromatic axes was recorded, and their performance was quantified using the binomial probability of their hits during the tests. Our results showed that dichromatic monkeys made more errors near the color confusion lines associated with their specific color vision genotypes, while the trichromatic monkey did not demonstrate any systematic errors. At high chromatic saturation, the trichromatic monkey had significant hits in the chromatic axes around the 180° chromatic axis, whereas the dichromatic monkeys had errors in colors around the color confusion lines. At lower saturation, the performance of the dichromatic monkeys became more challenging to differentiate among the three types, but it was still distinct from that of the trichromatic monkey. In conclusion, our findings suggest that high saturation conditions can be used to identify the color vision dichromatic phenotype of capuchin monkeys, while low chromatic saturation conditions enable the distinction between trichromats and dichromats. These results extend the understanding of color vision in New World Monkeys and highlight the usefulness of suprathreshold chromatic discrimination measures in exploring color vision in non-human primates.


Asunto(s)
Visión de Colores , Animales , Percepción de Color/fisiología , Sapajus apella , Genotipo , Cebus/genética , Platirrinos , Color
3.
Zoologia (Curitiba, Impr.) ; 40: e22023, 2023. graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1424771

RESUMEN

The giant river prawn, Macrobrachium rosenbergii (de Man, 1879), is a species of great commercial importance. It is farmed under different conditions that translate to a great range of light environments, which impact their behavior and productivity. We present the first study employing both visual modeling and beha vioral data to evaluate the ontogenetic changes in color preferences of juveniles and adults of M. rosenbergii. We offered ten shelters of different colors to juveniles and adults and registered their preferences. Our results show that shelter preference changed with ontogeny: juveniles chose shelters based on chromaticity (preference for blue), while adults based their decisions on brightness (preference for dark grey). This preference adults show for dark colors is probably associated with light avoidance behavior. We recommend providing blue shelters for juveniles and dark shelters for adults.(AU)


Asunto(s)
Animales , Conducta Animal , Acuicultura/métodos , Palaemonidae/genética , Estimulación Luminosa , Bienestar del Animal
4.
Rev. cuba. oftalmol ; 35(2)jun. 2022.
Artículo en Español | LILACS, CUMED | ID: biblio-1441730

RESUMEN

La pérdida no orgánica de la visión o pérdida funcional, es un trastorno en el cual se presenta cierta sintomatología visual, sin que haya causa alguna que pueda justificarlo. Se presenta un caso de una paciente adolescente femenina de 16 años de edad, color de piel blanca, con antecedentes oculares de ptosis palpebral derecha congénita y malos hábitos alimentarios. Su motivo de consulta fue pérdida de la visión de colores no constatada inicialmente; luego, debido a su insistencia, comenzamos a notar una disminución progresiva e incongruente de la visión cromática, con parámetros funcionales visuales normales, defectos en campos visuales computarizados no reproducibles y exámenes de electrofisiología visual normales, con recuperación total de este defecto sin tomarse ninguna conducta terapéutica específica. La pérdida no orgánica de la visión se refiere a cualquier defecto visual en la que no se demuestra alteración de las estructuras que se encuentran entre la córnea y la corteza cerebral occipital. Los trastornos de la vía aferente constituyen la manifestación más frecuente. Puede existir disminución, unilateral o bilateral, de la visión, afectación del campo visual o ambos. La visión de colores es usualmente anormal, pero rara vez, es el motivo de consulta. El origen psicógeno es corriente en niños y es más frecuente en mujeres que en hombres. El déficit adquirido de la visión de colores ocurre a consecuencia de una patología ocular, lesión intracraneal o uso excesivo de algún medicamento y, por lo general, se acompaña de pérdida variable de la agudeza visual(AU)


Non-organic loss of vision or functional loss is a disorder in which certain visual symptomatology is present, without any cause that could justify it. We present a case of a 16-year-old female adolescent patient, white skin color, with ocular history of congenital right palpebral ptosis and bad eating habits. Her reason for consultation was loss of color vision not initially detected; then, due to her insistence, we began to notice a progressive and incongruent decrease in color vision, with normal visual functional parameters, defects in non-reproducible computerized visual fields and normal visual electrophysiology tests, with total recovery of this defect without any specific therapeutic behavior. Non-organic vision loss refers to any visual defect in which no alteration of the structures between the cornea and the occipital cerebral cortex is demonstrated. Disorders of the afferent pathway constitute the most frequent manifestation. There may be unilateral or bilateral decreased vision, visual field impairment, or both. Color vision is usually abnormal, but rarely, it is the reason for consultation. Psychogenic origin is common in children and is more frequent in women than in men. Acquired color vision deficits occur as a consequence of an ocular pathology, intracranial injury or excessive use of medication and are usually accompanied by variable loss of visual acuity(AU)


Asunto(s)
Humanos , Femenino , Adolescente , Visión de Colores
5.
MedUNAB ; 25(1): 86-86, 202205.
Artículo en Español | LILACS | ID: biblio-1372317

RESUMEN

Con la técnica de aerografía sobre madera, se crea la obra "Daltonismo Racional", composición planteada en orden cartesiano, iniciando en el plano izquierdo superior con el panel rojo de línea totalmente quebrada, en constante zigzag, seguido a la derecha por el panel verde con gráfico de cigarrillo humeante; luego, en el sector izquierdo debajo del panel rojo encontramos el panel verde con la botella de licor y, finalmente, en la zona derecha inferior hallamos el panel con el gráfico del monitor rojo y línea blanca horizontal. Respecto a sus dimensiones, corresponde a un políptico conformado por cuatro módulos cuadrados, de 36 cm x 36 cm x 7 cm de profundidad. Entre los módulos hay un espacio de 20 cm, lo cual permite la formación de una cruz, por los dos espacios cruzados perpendicularmente. La obra tiene un carácter contestatario, frente a la manera como se pretende financiar la salud pública, debido a que los impuestos generados por la venta y consumo de alcohol y cigarrillos, se destinan para la salud, lo que nos lleva a una paradoja: ¿es razonable pensar que a través del detrimento de la salud de las personas que consumen licores y cigarrillos, se intente solucionar los problemas de salud?, ¿no es acaso la prevención y el no consumo de estas sustancias, lo que nos permite cultivar un mejor estado de salud?


With the technique of airbrushing on wood, the work "Rational Daltonism" is created. This is laid out in Cartesian order, starting on the upper left plane with the red panel with a totally broken line, in constant zigzag, followed to the right by the green panel with a graphic of a smoking cigarette; then, in the left sector below the red panel we find the green panel with the liquor bottle and, finally, in the lower right area we find the panel with the red monitor graphic and horizontal white line. Regarding its dimensions, it corresponds to a polyptych made up of four square modules, 36 cm x 36 cm x 7 cm deep. Between the modules there is a space of 20 cm, which allows the formation of a cross, by the two spaces crossed perpendicularly. The work has an anti-establishment character, as opposed to the way in which public health is intended to be financed, because the taxes generated by the sale and consumption of alcohol and cigarettes are destined for health, which leads us to a paradox: Is it reasonable to think that there is an attempt to solve health problems through the health detriment of the people who consume liquor and cigarettes? Is not prevention and not consuming these substances what allows us to cultivate a better health condition?


Com a técnica de aerografia sobre madeira, é criada a obra Daltonismo Racional. Esta está disposta em ordem cartesiana, iniciando no plano superior esquerdo com o painel vermelho com uma linha totalmente quebrada, em constante ziguezague, seguido à direita pelo painel verde com o gráfico de um cigarro fumando; em seguida, no setor esquerdo abaixo do painel vermelho encontramos o painel verde com a garrafa de licor e, finalmente, na área inferior direita encontramos o painel com o gráfico do monitor vermelho e linha branca horizontal. Quanto às suas dimensões, corresponde a um políptico composto por quatro módulos quadrados, com 36 cm x 36 cm x 7 cm de profundidade. Entre os módulos existe um espaço de 20 cm, que permite a formação de uma cruz, pelos dois espaços cruzados perpendicularmente. La obra tiene un carácter contestatario, frente a la manera como se pretende financiar la salud pública, debido a que los impuestos generados por la venta y consumo de alcohol y cigarrillos, se destinan para la salud, lo que nos lleva a una paradoja: es razonable pensar que a través del detrimento de la salud de las personas que consumen licores y cigarrillos, se intente solucionar los problemas de salud?, no es acaso la prevención y el no consumo de estas sustancias, lo que nos permite cultivar un mejor Estado de saúde?


Asunto(s)
Defectos de la Visión Cromática , Pintura , Arte , Consumo de Bebidas Alcohólicas , Uso de Tabaco
6.
J Addict Dis ; 40(4): 568-576, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35264083

RESUMEN

Chronic tobacco consumption, identified as Tobacco Use Disorder (TUD), is a public health problem. We present a case report of a 37-year-old Brazilian male diagnosed with TUD at age 26, with no comorbidities, that presented visual improvements (i.e., lower thresholds and better discrimination) after nicotine gum administration. Here, we assessed contrast sensitivity and chromatic discrimination using the Metropsis and the Cambridge Colour Test, respectively. Results showed lower thresholds for both visual tasks after the use of nicotine gum. Even considering this is a single case report, our intent is to open new avenues for research involving smoking, addiction and the use of nicotine gum as a replacement tool or adjuvant tool for improvement of visual and/or cognitive processing. It is well known that nicotine gum has protective effects for some diseases, and improves some cognitive functions. However, unclear were its effects on visual processing of people with TUD.


Asunto(s)
Cese del Hábito de Fumar , Tabaquismo , Adulto , Humanos , Masculino , Nicotina/uso terapéutico , Fumar/psicología , Cese del Hábito de Fumar/métodos , Dispositivos para Dejar de Fumar Tabaco , Tabaquismo/tratamiento farmacológico
7.
Front Aging Neurosci ; 14: 933453, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36688155

RESUMEN

Introduction: Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss in developed countries and one of the leading causes of blindness. In this work, we evaluated color vision and the pupil light reflex (PLR) to assess visual function in patients with early and neovascular AMD (NVAMD) compared with the control group. Methods: We recruited 34 early patients with dry AMD and classified them into two groups following AREDS: 13 patients with NVAMD and 24 healthy controls. Controls and patients with early dry AMD had visual acuity (VA) best or equal to 20/25 (0.098 logMAR). Color vision was assessed in controls and patients with early dry AMD using the Cambridge Color Test (CCT) 2.0 through the Trivector protocol. The PLR was evaluated using a Ganzfeld, controlled by the RETI-port system. The stimuli consisted of 1s blue (470 nm) and red (631 nm) light flashes presented alternately at 2-min intervals. To assess the cone contribution, we used a red flash at 2.4 log cd.m-2, with a blue background at 0.78 log cd.m-2. For rods, we used 470-nm flashes at -3 log cd.m-2, and for the melanopsin function of ipRGCs, we used 470 nm at 2.4 log cd.m-2. Results: Patients with early dry AMD had reduced color discrimination in all three axes: protan (p = 0.0087), deutan (p = 0.0180), and tritan (p = 0.0095) when compared with the control group. The PLR has also been affected in patients with early dry AMD and patients with NVAMD. The amplitude for the melanopsin-driven response was smaller in patients with early dry AMD (p = 0.0485) and NVAMD (p = 0.0035) than in the control group. The melanopsin function was lower in patients with NVAMD (p = 0.0290) than the control group. For the rod-driven response, the latency was lower in the NVAMD group (p = 0.0041) than in the control group. No changes were found in cone-driven responses between the control and AMD groups. Conclusion: Patients with early dry AMD present diffusely acquired color vision alteration detected by CCT. Rods and melanopsin contributions for PLR are affected in NVAMD. The CCT and the PLR may be considered sensitive tests to evaluate and monitor functional changes in patients with AMD.

8.
Heliyon ; 7(9): e08058, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34622063

RESUMEN

Color vision deficiency (CVD) is a frequent condition that alters color perception to such an extent that many people encounter serious difficulties on their everyday lives. In this work, we present a strategy to analyze the effectiveness of light filters aimed to improve color discriminability of persons with CVD. The calculations are based on a simple model of color discrimination which has been successfully applied to several animal species. We first tested the calculations on three well-known commercial lenses designed for persons with CVD. In agreement with results of clinical studies, the calculations show that the highly colored lenses (VINO® and X-Chrom®) enhance chromaticity contrasts between problematic colors, whereas the more neutral Enchroma® do not provide any benefit. Also, we predict that two light filters proposed in recent works for novel lenses would not improve the performance of the commercial ones. Since the mathematical approach presented in this work enables predictive filter assessment, it opens the door to future research on the design of more effective lenses to improve color discriminability of persons with CVD. The calculations allow for large-scale screening of numerous light filters and different colored stimuli, CVD conditions, light sources, etc.

9.
Behav Processes ; 192: 104496, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34492324

RESUMEN

A tail of conspicuous coloration is hypothesized to be an advantageous trait for many species of lizards. Predator attacks would be directed to a non-vital, and autotomizable, body part, increasing the chance of survival. However, as body size increases it also increases the signaling area that could attract predators from greater distances, increasing the overall chance of predation. Here, we test the hypothesis that there is a trade-off between tail color and size, affecting predation probabilities. We used plasticine replicas of lizards to study the predation patterns of small and large lizards with red and blue tails. In a natural environment, we exposed six hundred replicas to the attacks of free-ranging predators. Large red-tailed replicas were more attacked by birds. Mammals and unidentified predators showed no preference for any size or colors. The attacks were not primarily directed to conspicuous tails when compared to the bodies/heads of our replicas. Our study suggests that red color signals in large lizards could enhance their detection by visually oriented predators (i.e., birds). The efficacy of conspicuous tails as a decoy may rely on associated behavioral displays, which are hard to test with static replicas.


Asunto(s)
Lagartos , Animales , Aves , Pigmentación , Conducta Predatoria
10.
Behav Processes ; 192: 104495, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34487831

RESUMEN

In primates, the advantage of trichromacy (i.e., color vision expressed by most humans) over dichromacy (i.e., color vision expressed by many colorblind humans) has been linked to the detection of yellowish/reddish targets against a background of mature green leaves. Nevertheless, mostly because of studies conducted in humans, we know that achromatic cues might also play an important role in object identification, particularly when camouflage is involved. For instance, dichromacy favors the detection of camouflaged targets by exploitation of shape cues. The present study sought to evaluate the relative importance of color and shape cues on the detection of food targets by female and male marmosets (Callithrix jacchus). Animals were observed with respect to their foraging behavior and the number of food targets captured. We confirmed that females are advantageous in detecting conspicuous food against a green background and revealed that females and males rely on shape cues to segregate cryptic food. Unexpectedly, males outperformed females in cryptic food foraging, while camouflage improved males' (but not females') performance. Here we show that dichromats could potentially benefit from a better segregation of green natural targets (e.g., immature fruits, green insects, and gum trees) when viewed against a green dappled background.


Asunto(s)
Callithrix , Visión de Colores , Animales , Percepción de Color , Señales (Psicología) , Alimentos , Hojas de la Planta
11.
Ecol Evol ; 11(10): 5742-5758, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34026044

RESUMEN

A recent focus in community ecology has been on how within-species variability shapes interspecific niche partitioning. Primate color vision offers a rich system in which to explore this issue. Most neotropical primates exhibit intraspecific variation in color vision due to allelic variation at the middle-to-long-wavelength opsin gene on the X chromosome. Studies of opsin polymorphisms have typically sampled primates from different sites, limiting the ability to relate this genetic diversity to niche partitioning. We surveyed genetic variation in color vision of five primate species, belonging to all three families of the primate infraorder Platyrrhini, found in the Yasuní Biosphere Reserve in Ecuador. The frugivorous spider monkeys and woolly monkeys (Ateles belzebuth and Lagothrix lagotricha poeppigii, family Atelidae) each had two opsin alleles, and more than 75% of individuals carried the longest-wavelength (553-556 nm) allele. Among the other species, Saimiri sciureus macrodon (family Cebidae) and Pithecia aequatorialis (family Pitheciidae) had three alleles, while Plecturocebus discolor (family Pitheciidae) had four alleles-the largest number yet identified in a wild population of titi monkeys. For all three non-atelid species, the middle-wavelength (545 nm) allele was the most common. Overall, we identified genetic evidence of fourteen different visual phenotypes-seven types of dichromats and seven trichromats-among the five sympatric taxa. The differences we found suggest that interspecific competition among primates may influence intraspecific frequencies of opsin alleles. The diversity we describe invites detailed study of foraging behavior of different vision phenotypes to learn how they may contribute to niche partitioning.

12.
J. health sci. (Londrina) ; 23(1): https://revista.pgsskroton.com/index.php/JHealthSci/article/view/8195, 20210330.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1179425

RESUMEN

Dyschromatopsia is defined as an abnormality of color vision, a deficiency that can cause difficulties in the day-to-day of some careers in the health area, including medicine, as it makes clinical practice difficult and may lead to potential errors. The objective was identify the presence of Dyschromatopsias in the student and teaching community of UEMS Medicine School course and the repercussions they bring to the performance of activities related to medical activity. It is a quantitative, observational, cross-sectional and descriptive research. 160 individuals were evaluated, including Medicine School students and professors at the campus of UEMS - Campo Grande Unit, by reading pseudo-isochromatic slides from the Book of Ishihara. Data were tabulated in Excel and analyzed using non-parametric statistics. Of the 160 volunteers, 25 were professors (15.6%) and 135 students (84.3%). Most were female. Only 02 of the 58 volunteers (1.25%) surveyed, had color vision deficiency. Both patients with dyschromatopsia were already aware of their clinical conditions, and were classified in the research as having Deutan deficiency (green, red-green by Ishihara plates 16 and 17). The participants denied having a family history of this disease and both reported difficulties in the microscopies study and during medical prescriptions, due to the color of the pens to be used. The prevalence of Dyschromatopsias was 1.25%, and the 2 affected participants in the medical field already had knowledge of their disability. (AU)


Discromatopsia é definida como anormalidade da visão das cores, deficiência esta que pode causar dificuldades no dia-a-dia de algumas carreiras da área da saúde, incluindo medicina, pois dificulta a prática clínica e pode levar a potenciais erros. O objetivo foi identificar a presença de discromatopsias na comunidade discente e docente do curso de Medicina da UEMS e a repercussão que estas trazem para o desempenho das atividades relativas à atividade médica. Trata-se de uma pesquisa quantitativa, observacional, transversal e descritiva. Avaliou-se 160 indivíduos entre discentes e docentes de medicina do campus da UEMS ­ Unidade Campo Grande através da leitura de lâminas pseudo-isocromáticas do Livro de Ishihara. Dados foram tabulados em Excel e analisados via estatística não paramétrica. Dos 160 voluntários, 25 eram docentes (15,6%) e 135 discentes (84,3%), sendo que a maioria pertencia ao sexo feminino. Apenas 02 dos 58 voluntários (1,25%) pesquisados, apresentaram deficiência da visão de cores. Ambos os portadores de discromatopsia possuíam conhecimento de suas condições clínicas, e foram classificados na pesquisa como tendo deficiência Deutan (verde, vermelho-verde pelas placas 16 e 17 de Ishihara). Os participantes negaram ter histórico familiar deste acometimento e ambos referiram dificuldades no estudo das microscopias e durante as prescrições médicas, devido à cor das canetas a serem utilizadas. A prevalência das discromatopsias foi de 1,25%, e os 2 participantes afetados no meio médico já apresentavam conhecimento de sua deficiência. (AU)

13.
J Esthet Restor Dent ; 33(6): 865-873, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33125179

RESUMEN

OBJECTIVE: To evaluate the efficacy of visual discrimination tests used for color research in dentistry. MATERIALS AND METHODS: Volunteers (N = 120) were divided in three groups of observers (n = 40; gender-balanced): S-dental students; D-dentists; and L-laypersons. Two general color discrimination tests (I-Ishihara and FM-Farnsworth-Munsell 100 Hue) and the test of color discrimination competency in dentistry using the VITA Classical shade guide (VC) were performed and data were recorded according to manufacturers' or literature recommendations. Data were statistically analyzed using Mann-Whitney U test for the gender influence and Kruskal-Wallis test for the observer influence, and Bonferroni as post-hoc test (α = 0.05). Pearson (α = 0.05) was used to examine the correlation among visual tests (I, FM, and VC). RESULTS: Observers and visual tests were not influenced by gender (P > .05). Different observer groups had no influence on I test (P > .05). S and D showed similar level of color perception using FM and VC (P > .05), but these observers showed greater color perception than L (P ≤ .05). FM and VC also showed significant correlation (P ≤ .05) for the overall D observers (r = -0.362), male D (r = -0.594) and female S (r = -0.457). CONCLUSION: Observer experience significantly influenced on color perception, irrespective of gender. FM test showed greater correlation to color correspondence in dentistry (VC) than I test. CLINICAL SIGNIFICANCE: Observer experience is more relevant than gender for the color selection process in dentistry. Considering the visual discrimination tests for color research in dentistry, the Farnsworth-Munsell 100 Hue test seems to be more efficacious than the Ishihara test.


Asunto(s)
Percepción de Color , Percepción Visual , Color , Odontología , Femenino , Humanos , Masculino
14.
Am J Primatol ; 82(12): e23199, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32990997

RESUMEN

Vision is a major sense for Primates and the ability to perceive colors has great importance for the species ecology and behavior. Visual processing begins with the activation of the visual opsins in the retina, and the spectral absorption peaks are highly variable among species. In most Primates, LWS/MWS opsins are responsible for sensitivity to long/middle wavelengths within the visible light spectrum, and SWS1 opsins provide sensitivity to short wavelengths, in the violet region of the spectrum. In this study, we aimed to investigate the genetic variation on the sws1 opsin gene of New World monkeys (NWM) and search for amino acid substitutions that might be associated with the different color vision phenotypes described for a few species. We sequenced the exon 1 of the sws1 opsin gene of seven species from the families Callitrichidae, Cebidae, and Atelidae, and searched for variation at the spectral tuning sites 46, 49, 52, 86, 90, 93, 114, 116, and 118. Among the known spectral tuning sites, only residue 114 was variable. To investigate whether other residues have a functional role in the SWS1 absorption peak, we performed computational modeling of wild-type SWS1 and mutants A50I and A50V, found naturally among the species investigated. Although in silico analysis did not show any visible effect caused by these substitutions, it is possible that interactions of residue 50 with other sites might have some effect in the spectral shifts in the order of ~14 nm, found among the NWM. We also performed phylogenetic reconstruction of the sws1 gene, which partially recovered the species phylogeny. Further studies will be important to uncover the mutations responsible for the phenotypic variability of the SWS1 of NWM, and how spectral tuning may be associated with specific ecological features such as preferred food items and habitat use.


Asunto(s)
Opsinas de los Conos/genética , Variación Genética , Animales , Filogenia , Platirrinos , Análisis de Secuencia de ADN/veterinaria
15.
J Esthet Restor Dent ; 32(6): 601-606, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30593701

RESUMEN

OBJECTIVE: In patients with color vision alterations (CVA), the correct determination of color is altered, but not the detection of changes in luminosity or value. There is no accepted training protocol for dental value selection in dental students with CVA. The objective of this pilot study was to determine the effectiveness of a dental color training protocol based on the dental value selection. MATERIALS AND METHODS: An intervention study was carried out on dental students in a University setting, applying a specific dental color training protocol on two groups of students. Group 1:4 students with CVA, Group 2:4 healthy students. A third group of four students without intervention was used as a control group. An initial diagnostic test was applied, which was reapplied at the end of the training. RESULTS: The number of errors in the selection of the dental color decreased after training in all three groups, P > .05. For the value parameter, there was a statistically significant decrease in the number of errors after training (P = .014). CONCLUSIONS: The applied training protocol could be of help in students with CVA, but multicenter studies are needed. CLINICAL SIGNIFICANCE: Level 3 evidence level.


Asunto(s)
Visión de Colores , Coloración de Prótesis , Color , Percepción de Color , Educación en Odontología , Humanos , Proyectos Piloto , Estudiantes de Odontología , Enseñanza
16.
Vision Res ; 165: 13-21, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31610286

RESUMEN

Single-cell recordings in the primary visual cortex (V1) show neurons with spatial frequency (SF) tuning, which had different responses to chromatic and luminance stimuli. Visually evoked cortical potential (VECP) investigations have reported different spatial profiles. The current study aimed to investigate the spatial selectivity of V1 to simultaneous stimulus of chromatic and luminance contrasts. Compound stimuli temporally driven by m-sequences at 8 SFs were utilized to generate VECP records from thirty subjects (14 trichromats and 16 colorblind subjects). We extracted the second-order kernel, first and second slices (K2.1 and K2.2, respectively). Optimal SF, SF bandwidth, and high SF cut-off were estimated from the best-fitted functions to the VECP amplitude vs SF. For trichromats, K2.1 waveforms had a negative component (N1 K2.1) at 100 ms followed by a positive component (P1 K2.1). K2.2 waveforms also had a negative component (N1 K2.2) at 100 ms followed by a positive deflection (P1 K2.2). SF tuning of N1 K2.1 and N1 K2.2 had a band-pass profile, while the P1 K2.1 was low-pass tuned. P1 K2.1 optimal SF differed significantly from both other negative responses and from P1 K2.2. We found differences in the optimal SF, SF tuning and high SF cut-off among the VECP components. Dichromats had little or no response for all stimulus conditions. The absence of the responses in dichromats, the similarity between the high SF cut-off of the pseudorandom VECPs and psychophysical chromatic visual acuity, and presence of multiple SF tunings suggested that pseudorandom VECPs represented the activity of cells that responded preferentially to the chromatic component of the compound stimuli.


Asunto(s)
Percepción de Color/fisiología , Potenciales Evocados Visuales/fisiología , Corteza Visual/fisiología , Vías Visuales/fisiología , Humanos , Estimulación Luminosa
17.
Rev. bras. oftalmol ; 78(5): 304-309, Sept.-Oct. 2019. graf
Artículo en Portugués | LILACS | ID: biblio-1042380

RESUMEN

Resumo Por conta de uma doença ocular, a obra de Monet foi analisada por múltiplas facetas, incluindo o reflexo da deterioração de sua visão nos seus trabalhos, motivo deste trabalho de revisão. Tendo como referência este panorama, propõe-se aqui pensar, por meio de algumas obras marcantes da biografia de Monet, a doença ocular catarata e o seu papel na história de vida deste pintor.


Abstract Due to the ocular disease, Monet's work was analyzed by multiple facets, including the reflection of the deterioration of his vision in his works, reason for this work of revision. With reference to this panorama, it is proposed here to think, by means of some remarkable works of the biography of Monet, the ocular cataract disease and the paper of this in the history of this painter's life.


Asunto(s)
Pinturas/historia , Catarata/historia , Extracción de Catarata/historia , Personajes , Visión de Colores , Catarata/complicaciones , Agudeza Visual , Defectos de la Visión Cromática , Percepción de Color , Historia del Siglo XIX , Historia del Siglo XX
18.
Rev. bras. oftalmol ; 78(4): 242-245, July-Aug. 2019.
Artículo en Inglés | LILACS | ID: biblio-1013681

RESUMEN

ABSTRACT Objective: The goal of the study is to analyze the color vision acuity pattern in undergraduates of health courses and to discuss the impact of these diseases in this population. Color deficiencies interfere significantly in the daily routine of professionals in the health area who need to discern different color hues in several situations of their everyday practice. Methods: Sixty-four volunteers, undergraduates of health courses of the Federal University of Alfenas (UNIFAL-MG), participated in the study. One man was excluded because he did not fit the inclusion criteria. Two groups were analyzed according to sex with the Farnsworth Munsell 100-Hue test. Results: There were no significant differences between the eyes and between the groups analyzed. The color vision acuity pattern is between 35 and 40, according to the Total Error Score. The gender issue does not influence the general pattern of the color vision acuity of the health courses undergraduates when those with color vision disorders are removed. Conclusion: Screenings and guidance should be given to undergraduates of health courses so that, aware of their condition of presenting some type of color disorder, they shall make the appropriate decision on which career to follow so that such limitation does not interfere with the quality of their daily life.


RESUMO Objetivo: O objetivo do estudo é analisar a acuidade visual média para cores de estudantes da área de saúde e discutir o impacto das doenças que a afetam nessa população. Deficiências cromáticas interferem de forma significativa no dia a dia de profissionais da área da saúde que necessitam de discernir diferentes matizes em diversas situações de sua prática profissional. Métodos: Participaram da pesquisa 64 voluntários, estudantes de cursos da área de saúde da Universidade Federal de Alfenas, sendo que 1 homem foi excluído por não se adequar aos critérios de inclusão. Dois grupos foram analisados, de acordo com o sexo, com o teste de Farnsworth Munsell 100-Hue. Resultados: Não houve diferenças significativas entre os olhos e entre os grupos analisados. O padrão de visão de cores encontra-se entre 35 e 40, de acordo com a Pontuação do Erro Total. A questão de gênero não influencia no padrão geral da qualidade de visão de cores de estudantes da área de saúde, quando retirados aqueles que apresentam distúrbios da visão cromática. Conclusão: Devem ser realizadas triagens e orientação para estudantes de cursos da área de saúde para que, cientes da sua condição de apresentar algum tipo de distúrbio cromático, possam tomar a decisão adequada sobre qual carreira seguir para que tal limitação não interfira na qualidade de sua vida diária.


Asunto(s)
Humanos , Masculino , Femenino , Estudiantes del Área de la Salud , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/epidemiología , Personal de Salud , Pruebas de Percepción de Colores/métodos , Competencia Profesional , Calidad de Vida , Escuelas para Profesionales de Salud , Agudeza Visual , Selección Visual , Defectos de la Visión Cromática/psicología , Diagnóstico por Computador/métodos , Percepción de Color/fisiología , Visión de Colores/fisiología
19.
Cad. Bras. Ter. Ocup ; 27(2): 367-371, abr.-jun. 2019. tab, graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1011686

RESUMEN

Resumo Introdução Evidências têm apontado que a preferência visual por cores em crianças com desenvolvimento atípico pode ser diferente, quando comparada à criança sem alterações do desenvolvimento. Embora esse dado representa um importante mediador sobre a trajetória do desenvolvimento, nenhum estudo caracterizou este perfil em recém-nascidos (RN). Objetivo Caracterizar a preferência visual por cores em RN termo nas primeiras horas de vida. Método Estudo transversal com 46 RN posicionados no colo das mães. Para a avaliação da preferência visual por cores foram apresentados seis cartões, sendo metade branca e a outra metade na cor cromática. A prevalência entre as cores foi testada pelo teste Qui-quadrado e considerou-se o nível de significância de 5%. Resultados 75% dos RN preferiram a cor azul (p=0,001) e apesar da frequência do olhar entre a cor verde e branca ser maior para a cor cromática, não foi detectado preferência entre esta análise (p=0,23). Os únicos cartões que as frequências foram maiores para a o branco foram os cartões com cores amarela e laranja e, ainda assim, não há preferência entre elas (p=0,05 e p=0,37, respectivamente). Conclusão Foi possível conhecer a preferência cromática pelo azul em RN já nas primeiras horas de vida. Considerando que os problemas detectados e ganhos visuais que acontecem ainda no período neonatal irão interferir no desenvolvimento para a vida adulta, sugere-se que uma avaliação da preferência visual por cores possa ser incorporada na rotina do terapeuta ocupacional da Unidade Neonatal, mesmo quando o público alvo for um RN com poucas horas de vida.


Abstract Introduction Evidence has indicated that the visual preference for color in children with atypical development may be different, when compared with child without developmental changes. Although this data represents an important mediator on the developmental trajectory, no study has characterized this profile in newborns (NB). Objective To characterize visual preference for color in full-term NB in the first hours of life. Method This is a cross-sectional study with 46 NBs. Six cards were presented to evaluate the visual chromatic preference, being half white and half in chromatic color. To compare the prevalence of color choice, the chi-square test was applied and the significance level of 5% was considered. Results It was found that 75% of the NBs preferred the color blue (p=0.001) and although the visual frequency between green and white color was higher for chromatic color, no preference was detected (p=0.23). The only cards that had visual frequency higher for white color were yellow and orange, but no preference between them (p=0.05 and p=0.37, respectively). Conclusion The chromatic preference for blue in NBs in the first hours of life was observed. Considering that visual problems and visual gains during neonatal period will interfere with development into adult life, it is suggested that an assessment of visual color preference can be incorporated into the routine of the Neonatal occupational therapist even the NB has few hours of life.

20.
Front Neurosci ; 13: 179, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30894798

RESUMEN

Chronic alcohol abuse can lead to a brain damages, and the health status of alcoholics even after a long-term alcohol abstinence is a public health concern. The present study investigated the color vision and spatial luminance contrast sensitivity of a group of 17 ex-alcoholics (46.3 ± 6.7 years old) in long-term alcohol abstinence after having been previously under alcohol dependence for many years. We also investigated the association of impaired psychophysical performance in different tests we applied. The mean time of alcohol consumption was 16.9 ± 5.1 years and the mean abstinence period was 12.4 ± 8.5 years. Achromatic vision of all subjects was evaluated using spatial luminance contrast sensitivity function (CSF) test and color vision was evaluated using Mollon-Reffin color discrimination test (MR) and the Farnsworth-Munsell 100 hue arrangement test (FM100). Relative to controls, the spatial luminance contrast sensitivity was lower in 10/17 of the ex-alcoholic subjects. In the color vision tests, 11/16 ex-alcoholic subjects had impaired results compared to controls in the FM100 test and 13/14 subjects had color vision deficits measured in the MR test. Fourteen subjects performed all visual tests, three subjects had impaired results for all tests, seven subjects had impaired results in two tests, three subjects had visual deficit in one test, and one had normal results for all tests. The results showed the existence of functional deficits in achromatic and chromatic vision of subjects with history of chronic alcoholism after long abstinence. Most subjects had altered result in more than one test, especially in the color vision tests. The present investigation suggests that the damage in visual functions produced by abusive alcohol consumption is not reversed after long term alcohol abstinence.

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