Navegando por Palavras-chave "Psychophysics"

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    Elaboração e validação de tabela MNREAD para o idioma português
    (Conselho Brasileiro de Oftalmologia, 2005-12-01) Castro, Celina Tamaki Monteiro de [UNIFESP]; Kallie, Christopher Scott; Salomão, Solange Rios [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); University of Minnesota
    PURPOSE: To create and to validate a version of the Minnesota Low Vision Reading Test (MNREAD) acuity chart for the Portuguese language. METHODS: The Minnesota Low Vision Reading Test acuity chart contain 19 sentences (logMAR 0.5 to 1.3) with 60 characters printed on three lines. All the sentences must have the same length with simple vocabulary. A total of 110 sentences were generated. The sentences were presented to 36 subjects (20 adults and 16 children) and mistakes and reading time were marked. 38 sentences were selected for a prototype (MNREAD-P). Sentences with extreme high and low mean reading time, large standard deviation, and with persistent mistakes by subjects were excluded. Validation: Twenty subjects with normal vision (logMAR 0 or 20/20 or better, with best refractive correction) were tested with the MNREAD-P and read a passage of text, representing normal, day-to-day reading. Reading speeds in words per minute were recorded for both the MNREAD and the text passage. RESULTS: Sentences in the MNREAD Portuguese chart are sufficiently consistent to provide reliable measures of reading abilities. Reading speeds for the passage (logMar = 0.6) were 197.8 words/minute and the maximum reading speeds calculated by the MNREAD-P were 200.1 words/minute. The correlation between the two measures was r = 0.82. CONCLUSION: The MNREAD-P was tested on normal vision subjects and the results were the same from the original Minnesota Low Vision Reading Test. The reading speed measured on the MNREAD-P was statistically equivalent to the reading speed of the passage.
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    Medida da visão em candelas: descrição de uma técnica psicofísica para quantificar intensidade luminosa
    (Consel Brasil Oftalmologia, 2011-03-01) Kronbauer, Airton Leite [UNIFESP]; Schor, Paulo [UNIFESP]; Chamon, Wallace [UNIFESP]; Carvalho, Luis Alberto Vieira de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    Purpose: To develop a method and a device for vision measurement in candela (cd). Vision measurement studies are important to all visual sciences.Methods: It is a theoretical and experimental study. The details of psychophysical method and device calibration were described. Preliminary tests were performed on volunteers.Results: It is a simple psychophysical test and results are expressed in International System of Units. With this technical description it will be possible to reproduce the experiment in others research centers.Conclusion: The results measured in luminous intensity (cd) are an option for visual studies. These results allow to extrapolate measurements for mathematical models and to simulate data for individual aberrometry effects.