Navegando por Assunto "Cambridge Colour Test"

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Acesso aberto (Open Access)
Comparação de dois procedimentos computadorizados para avaliação de discriminação de cores em Cebus sp
(Universidade Federal do Pará, 2009-11) MAKIAMA, Sheila Tetsume; GOULART, Paulo Roney Kilpp; http://lattes.cnpq.br/7800966999068746; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
Color vision consists in discrimination of objects based on their spectral composition, assisting in the organism-environment interaction. Among primates, it is estimated that the majority of the platyrrhines monkeys has a polymorphic and sex-linked dichromacy. The objective of this study was to compare the results produced by different equipments and softwares for assessment of tri/dichromatic conditions of two males and two females of the genus Cebus sp. Two computerized programs were used: one involving an adapted version of the Cambridge Colour Test and another one developed for a standard computational system. In Experiment 1 and 2 were possible to verify the trichromatic condition of one female subject and the dichromatic condition of the rest of the participants. In Experiment 3, a female and a male subject presented a dichromatic performance compatible to that one registered in previous experiments. In this Experiment, a female participant presented a trichromatic performance compatible to that one registered in previous experiments. It was concluded that favorable conditions for assessment of color vision in platyrrhines species can be built involving equipment and software with low financial cost and easy to program. However, due the few number of sessions with the low financial cost equipment, it is suggested the replication of the Experiment 3 and more sessions should be made with more subjects and involving new stimuli arrangement. It is believed that, if new data confirm the data produced here, this equipment and procedure can be used for evaluation of others platyrrhines species where behavioral data are scarce.
Acesso aberto (Open Access)
Comparison of two computerized procedures for the assessment of color discrimination in Cebus apella
(2011-12) MAKIAMA, Sheila Tetsume; GOULART, Paulo Roney Kilpp; GALVÃO, Olavo de Faria
Color vision consists of the discrimination of objects based on their spectral composition. Among primates, the majority of Platyrrhini monkeys are estimated to have polymorphic and sex-linked dichromacy. The objective of this study was to compare the results produced by different equipment and software for the assessment of tri- and dichromatic conditions in one male and two female Cebus apella. Three experiments were programmed. In Experiment 1, verifying the trichromatic condition of one female subject and dichromatic condition of the remainder of the subjects was possible using an adapted version of the Cambridge Colour Test. Experiment 2 confirmed the results of Experiment 1 using a different array of stimuli of the same test. Experiment 3, which produced results similar to Experiment 2, consisted of a test developed for a standard computer system using stimuli with color properties similar to the ones used in the previous experiment. Favorable conditions for the assessment of color vision in Platyrrhini can be built with low-cost equipment and software. Once data have been gathered with additional subjects and new stimulus arrangements have been tested and confirmed, the procedure can be used for the evaluation of other Platyrrhini species for which behavioral color discrimination data are currently lacking.
Acesso aberto (Open Access)
Correlação entre parâmetros estimados pelos testes Colour Assessment and Diagnosis e Cambridge Colour Test na avaliação da discriminação de cores
(Universidade Federal do Pará, 2015-03-31) FARIAS, Letícia Miquilini de Arruda; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718
The Colour Assessment and Diagnosis (CAD) and Cambridge Colour Test (CCT) tests are widely used in basic and clinic researches, because of high sensibility and specificity of your results. These tests use distinct paradigms of stimulation to estimate the color discrimination thresholds. It is not well known about the relationship of results of each paradigm in the evaluation of color discrimination in these tests. So, the present study aimed to compare the parameters of evaluation of color discrimination estimated from CAD and CCT tests. Fifty-nine trichromat subjects and thirty eight subjects with congenital dyschromatopsia (16 protans, 22 deutans) with mean age of 26,32 ±8,9 years-old were evaluated. 66 subjects were tested in CAD and CCT tests, 29 subjects in the CAD test and 2 subjects in the CCT test. The color vision phenotype of all subjects was determined through a battery of psychophysical tests and the estimative of color discrimination thresholds was evaluated by CAD and CCT tests. The data of color discrimination thresholds was fitted ellipses. The criteria analyzed to each subject were: area of the ellipses, angle of rotation of the ellipses and size of protan, deutan and tritan vectors. For each one of parameters was realized: descriptive statistic, analysis of dispersion of parameters between CAD e CCT tests and the combination of these parameters in each test, ratio between the parameters, correlation of parameters to three mathematical models and analysis of agreement. The parameters of area and size of deutan and tritan vectors of trichromat subgroup, area and size of tritan vector of protan subgroup, and size of protan and tritan vectors of deutan subgroup exhibited equivalence between the results of both tests. The parameters of area, angle of rotation and size of protan and tritan vectors showed agreement of measures between your results. Factors as the distincts localizations of neutral points of CAD and CCT tests and the spatial arrangement of the vectors in the CIE 1976 color space in the CCT test may have influenced the determination of chromatic discrimination thresholds of both tests. Despite using distinct paradigms in configuration of stimulation, the tests CAD and CCT are comparable.
Acesso aberto (Open Access)
Um teste computadorizado para a avaliação de visão de cores em crianças e sujeitos não-verbais baseado no teste de discriminação de cores de Mollon-Reffin
(Universidade Federal do Pará, 2008-12-16) GOULART, Paulo Roney Kilpp; SILVEIRA, Luiz Carlos de Lima; http://lattes.cnpq.br/9383834641490219; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
The present study aimed at providing conditions for the assessment of color discrimination in children using a modified version of the Trivector mode of the Mollon-Reffin color discrimination test. Since the task of indicating the gap of the Landolt C used in that test proved counterintuitive and/or difficult for young children to understand the target stimulus was changed to a square patch of color the subjects were asked to touch. The Trivector test measures color discrimination for the protan, deutan and tritan confusion lines. Experiment I sought to evaluate the correspondence between the CCT and the child-friendly adaptation with adult subjects (n=29) with normal color vision. Comparison of the thresholds obtained with both tests using Bland-Altman statistical methods showed good agreement between the two test versions. Experiment II tested the child-friendly software with children 2 to 7 years old (n=25) using operant training techniques for establishing and maintaining the subjects‟ performance. Color discrimination thresholds were progressively lower as age increased. The protan and deutan thresholds were consistently lower than tritan thresholds, a pattern repeatedly observed in adults tested with the CCT. The results demonstrate that the test is fit for assessment of color discrimination in young children and may be a useful tool for the establishment of color vision thresholds during development, as well as for use with other human populations, as well as with other primate species. (CNPq, FINEP).