Search results for "Trichromacy"
showing 6 items of 6 documents
Three-dimensional interpretation of the color system of Aguilonius/Rubens 1613
2000
The two-dimensional color system in the textbook on optics, written by F. Aguilonius (1613) and illustrated by PP Rubens,1 is equivalent to a three-dimensional color solid, which can also be constructed by applying the trichromatic theory of color vision on a color circle. © 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S17–S19, 2001
Color memory matching in normal and red-green anomalous trichromat subjects
2001
The methods of simultaneous and successive color matching have been studied for a set of seven color reference samples by 15 protanomalous and 21 deuteranomalous trichromat subjects. From comparison between both populations and a group of 25 trichromat normal ones, investigated previously under similar experimental conditions [J. Perez–Carpinell et al. Color memory matching: time effect and other factors. Color Res Appl 1998;23:234–247], we can deduce the following. (a) For anomalous trichromat populations, as with a normal one, we find significant differences between simultaneous and successive color matching, p < 0.05. (b) If we consider the average of all the colors, we find that, while …
Dopamine antagonists impair ‘red-green’ discrimination in goldfish after intravitreal injection
1995
Color vision in goldfish is tetrachromatic. However, under mesopic illumination conditions the L-cones do not contribute to wavelength discrimination, and color vision becomes trichromatic. To investigate the role of dopamine in light adaptation, we tested the effect of the unspecific dopamine antagonist haloperidol and of the specific dopamine Dl receptor antagonists SCH 23390 and SKF 83566-biotinyl in behavioral wavelength discrimination experiments. After injection of dopamine antagonists into the vitreous, a reduction in wavelength discrimination was observed in the range between 560 nm and 630 nm but not in the range between 404 nm and 501 nm.
Color memory in protanomals and deuteranomals: Matching time effect
2003
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…
Trichromatic color vision in the salamander (Salamandra salamandra)
1995
Spectral sensitivity functions were measured between 334 nm and 683 nm in Salamandra salamandra by utilizing two behavioral reactions: the negative phototactic response, and the prey catching behavior elicited by a moving worm dummy. The action spectrum of the negative phototactic response revealed 3 pronounced maxima: at 360–400 nm, at 520–540 nm, and at 600–640 nm. In the range around 450 nm, there was a “reaction gap” where sensitivity could not be measured. The action spectrum of the prey catching behavior was entirely different: maximal sensitivity was found at 500 nm and at 570 nm. Between 500 nm and 334 nm sensitivity decreased continuously for about 1 log unit (Fig. 6).
Color induction via non-opponent lateral interactions in the human retina
1992
Retinal connections causing colors in Benham's top (pattern induced flicker colors, PIFCs) are investigated by psychophysical experiments. PIFCs are still seen when stimuli to different cones are demodulated selectively, indicating the involvement of non-opponent channels. PIFCs also occur on retinal areas next to those affected by modulated stimuli; further, both monochromat and dark-adapted trichromats perceive PIFCs which are achromatic. These additional findings point to horizontal cells as neuronal mediators of modulated excitation leading to PIFCs. The unspecifity of the postulated connection with respect to cone types agrees with anatomic findings of Boycott, B. B., Hopkins, J. M. an…