Related Experiment Video
Updated: May 12, 2026
06:50
Enabling High Grayscale Resolution Displays and Accurate Response Time Measurements on Conventional Computers
Published on: February 29, 2012
Simultaneous brightness and apparent depth from true colors on grey: Chevreul revisited
Birgitta Dresp-Langley1, Adam Reeves
1Centre National de la Recherche Scientifique (CNRS UMR 5508), Montpellier, France. birgitta.dresp-langley@univ-montp2.fr
Seeing and Perceiving
|April 5, 2013
Summary
True colors create unexpected brightness changes on grey backgrounds, revealing simultaneous assimilation and contrast effects. Luminance contrast, not adaptation, determined perceived depth, challenging existing visual theories.
Area of Science:
- Visual perception
- Color science
- Psychophysics
Background:
- Simultaneous brightness induction, as defined by Chevreul, involves how colors affect adjacent grey backgrounds.
- Both assimilation and apparent contrast can occur within the same visual display.
- The relationship between these induction effects and perceived depth requires further investigation.
Purpose of the Study:
- To investigate simultaneous brightness induction effects of true colors on grey backgrounds.
- To examine the link between induction effects and perceived depth as a function of luminance contrast.
- To explore the influence of adaptation states and display configurations on these phenomena.
Main Methods:
- Participants viewed square-shaped colored or grey inducers on grey backgrounds under varying luminance contrasts and adaptation conditions (dark-adaptation, daylight, rod-saturation).
- Forced-choice tasks measured probabilities of contrast, assimilation, and perceived depth (nearer/farther).
- Display configurations included spatially separated or single background fields.
Main Results:
- Colored inducers produced simultaneous induction effects, with assimilation and contrast co-occurring.
- Perceived depth was solely determined by inducer luminance contrast, with brighter inducers perceived as nearer.
- Achromatic inducers showed stronger contrast in dark-adaptation and stronger assimilation in daylight; grouping backgrounds reduced contrast effects.
Conclusions:
- Simultaneous induction effects are influenced by color and luminance contrast, impacting perceived depth.
- Findings challenge theories linking induction effects directly to perceived surface depth.
- The study highlights the complexity of color interactions in visual perception.
Related Concept Videos
01:12Perceptual Constancy
Perceptual constancy is the ability to recognize that objects remain consistent and unchanged even when their appearance varies due to changes in sensory input. There are four main types of perceptual constancy: size constancy, shape constancy, color constancy, and brightness constancy.
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
01:15Depth Perception and Spatial Vision
Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.
01:24Color Vision
Color perception begins in the retina, the light-sensitive layer at the back of the eye. Two main theories explain how colors are seen: the trichromatic theory and the opponent-process theory. The trichromatic theory, proposed by Thomas Young in 1802 and extended by Hermann von Helmholtz in 1852, suggests that color vision is based on three types of cone receptors in the retina. These cones are sensitive to different but overlapping ranges of wavelengths corresponding to red, blue, and green.
01:21Gestalt Principles of Perception
Gestalt principles provide a framework for understanding how humans perceive objects as unified wholes within their context. These principles are essential in explaining the cognitive processes that make sense of complex visual stimuli by organizing them into coherent groups. One fundamental principle is proximity, which posits that objects located close to each other are perceived as a collective group. For instance, when dots are positioned near one another, the visual system interprets them...
01:17Convolution Properties II
The important convolution properties include width, area, differentiation, and integration properties.
The width property indicates that if the durations of input signals are T1 and T2, then the width of the output response equals the sum of both durations, irrespective of the shapes of the two functions. For instance, convolving two rectangular pulses with durations of 2 seconds and 1 second results in a function with a width of 3 seconds.
The area property asserts that the area under the...
The width property indicates that if the durations of input signals are T1 and T2, then the width of the output response equals the sum of both durations, irrespective of the shapes of the two functions. For instance, convolving two rectangular pulses with durations of 2 seconds and 1 second results in a function with a width of 3 seconds.
The area property asserts that the area under the...
01:26Phase Contrast and Differential Interference Contrast Microscopy
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...