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Foveal and peripheral hue-scaling data were obtained for a 1° foveal stimulus and a 3° stimulus presented at 10° retinal eccentricity under both bleach (reducing rod input) and no-bleach (permitting rod input) conditions. Uniform appearance diagrams (UADs) were generated from the data. Peripheral stimuli appeared more saturated than foveal stimuli (i.e., supersaturated), especially in the green-yellow region of the UADs. This effect was particularly pronounced for the peripheral bleach condition. The range of wavelengths perceived as green-yellow in the peripheral retina was expanded as compared to the fovea, while the range of wavelengths experienced as blue-green was compressed. This indicates that there are shifts in the unique hue loci with retinal location. While several factors can be ruled out as potential causes for these perceptual differences, the underlying mechanism of this supersaturation effect in the peripheral retina is unknown.

Hue perception has been shown to differ for the same stimulus when presented to the temporal and the nasal areas of the retina. The present study investigated perceptual differences in stimuli viewed binocularly or monocularly in the peripheral retina to determine how hue information combines across the two retinas for a stimulus falling on the temporal retina of one eye and the nasal retina of the other. A hue-scaling procedure was utilized to ascertain hue perception for three color- and binocular-normal observers viewing monochromatic stimuli (450-670nm, 20nm steps) ranging in size from 1.0° to 3.7°. Peripherally-presented binocular stimuli fell upon the nasal retina of one eye and the temporal retina of the other. Hue-scaling results indicated that peripheral binocular hue and saturation perceptions for smaller stimuli were more similar to those of stimuli falling on the temporal retina in the monocular condition. Hue-scaling data were also used to determine perceptive field sizes for the four elemental hues. Binocular perceptive field sizes were more similar to those obtained for stimuli falling on the temporal retina in the monocular conditions. Eye dominance did not appear to have an effect on hue perception. The results seem to indicate that visual information from the temporal retina is weighted more heavily when information from the two eyes is combined cortically. This finding may relate to differences in V1 cortical activation for stimuli presented to the nasal retina versus the temporal retina.

Time is inside as well as outside of ourselves. Time is a perception. It is part of the outside world, but it is also a sensation immediately experienced in ourselves. We organize and crystalize the perception of time into the connotation of a continuous flowing time, which we measure by clocks, and we try to apply the same measures to the time experience in ourselves, to what we may call time sensation…. Time is an inherent part of the world of perception, outside and inside the body.

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