| Autor: |
Stephen J. Dain, D. H. Foster, M. O. Scase |
| Rok vydání: |
1991 |
| Předmět: |
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| Zdroj: |
Documenta Ophthalmologica Proceedings Series ISBN: 9789401056809 |
| DOI: |
10.1007/978-94-011-3774-4_23 |
| Popis: |
The colour-vision losses in blue-yellow acquired colour-vision deficiencies have been likened to the performance of normal subjects at low luminance levels and described as a ‘mesopization’. The B-Y colour-vision deficiency seen in diabetic patients has been shown to be enhanced when short-duration stimuli are used in patients without retinopathy (Scase et al., 1990). To assess whether mesopization can also explain losses with brief stimuli, hue-discrimination performance was determined along the cardinal directions of colour space in subjects with normal colour vision over a range of luminances from 7.0 to 0.025 cd m-2. Stimuli were presented on a colour video-display system. This technique has the advantage, unlike the Farnsworth-Munsell 100-Hue Test on which the mesopization hypothesis was based, of having no possible bias towards B-Y thresholds compared with red-green thresholds when screen luminance was reduced. This was true for both long- and short-duration stimuli. Therefore mesopization cannot account for the specific deficits in B-Y discrimination previously demonstrated by this technique in diabetic patients, especially those found with short-duration stimuli in patients without retinopathy. A specific loss in blue-yellow processing is indicated. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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