Visual defects in subjects with Down’s syndrome

Because the incidence of other visual defects is much higher in cases of Down’s syndrome than in individuals with other forms of retardation (Gardiner, 1967; Aitchison et al., 1990), we tested the color vision of a population of Down’s syndrome patients, using Ishihara plates and the Davico anomaloscope. The Down’s syndrome group had a significantly higher proportion of color deficiencies than either normal controls or a matched mentally retarded population. Refractive errors were corrected with static retinoscopy, and spatial contrast sensitivity was measured with the Vistech test.

Color memory in protanomals and deuteranomals: Matching time effect

In a companion paper Perez-Carpinell et al., Color Res Appl 2001;26:158–170, for a set of seven color references, we compared the methods of simultaneous and memory color matching by 15 protanomals and 21 deuteranomals, looking for differences between them and a group of 25 normal trichromat observers investigated previously Perez-Carpinell et al., Color Res Appl 1998;23:234–247. In our current article, matching times of the same anomalous trichromat groups, and with the same reference tests, to select from among the comparison chips the one that most resembled one of the seven reference tests, have been measured under simultaneous and successive color matching procedures. From comparison b…

Vision evaluation in people with Down's syndrome.

We tested the colour vision of 72 people with Down's syndrome using the Ishihara test and an anomaloscope. We found that 13 of the subjects, 6 males and 7 females, had defective colour vision according to Pickford's classification. In monocular vision 10 eyes were protan (five simple, three extreme and two deviant), one eye was simple deuteranomalous and the remaining eyes were normal: in binocular vision four of the subjects were protan (two simple and two deviant), two subjects were deutan (one simple and one deviant) and the rest were normal. Many of our subjects had lens opacities, strabismus, nystagmus, hypermetropia, high myopia and astigmatism, confirming literature reports. The cont…

Psychological factors and defective colour vision

In this study, involving students between 14 and 16 years old, the psychological dimensions of cognition and personality affected by red-green colour vision deficiencies were investigated. From the results of a factorial analysis it appears that the influence of colour vision abnormality on the psychological factors that we tested is always minor. Colour vision defect is correlated with such cognitive variables as spatial aptitude and visual difference perception, and with such personality variables as praxemia and submission. The weighting of the cognition and personality factors linked to colour vision abnormality, however, varies considerably and does not in any case contribute more than…

Asymmetric colour matching: memory matching versus simultaneous matching

We have compared corresponding pairs obtained by simultaneous matching (haploscopic matching) and by memory matching (after 10 min) using 34 reference tests selected from the Munsell Atlas (glossy), belonging to the four main hues 5Y, 5G, 5PB, and 5RP. These colours lie very close to the F1 and F2 axes in the SVF space, where we have analyzed our results. Illuminants D65 and A were used as reference and matching illuminants, respectively. Our results show for both kinds of matching a tendency to select more colourful colours than the original ones, with significant differences between matching and test colours, whereas hue does not seem to follow a definite pattern. This behavior is similar…

Familiar objects and memory color

This research was supported in part by a grant from ADEIT- Universitat de Valencia and IMPIVA to M.D. de F.

Color memory matching: Time effect and other factors

The methods of simultaneous and successive, or memory, color matching have been compared for 10 color reference samples distributed in two groups each performed by 50 observers (25 men and 25 women). Our results, obtained with a total of two hundred Munsell color chips arrayed on ten gray cardboard panels, indicate that: (a) while by simultaneous matching the mean color differences obtained are, in most cases, lower than 1 CIELAB unit, those obtained by memory are generally higher; (b) the worst remembered colors are yellow, light green, blue, and pink, and the best remembered color is orange; (c) the influence of the delay time (15 s, 15 min, and 24 h) is significant for the remembered mea…

Color memory in elderly adults

Color memory in children

The methods of simultaneous and memory color matching have been studied for a set of five Munsell color samples by 50 children, 25 boys and 25 girls (ranging in age from 9 to 11 years). By comparison between this group and one of 50 young adult observers, we can deduce the following: (a) In children, as in young adults, the mean CIELAB total color difference, ΔE*ab, in simultaneous color matching is lower than the ΔE*ab by memory color matching. (b) Children matched reference test worse than young adults for orange, bluish green (only boys and men) and yellow green (only girls and women). (c) While men remember, independently of age and delay time, violet reference test worse than women (P …