Color
The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.
Color Perception
Mental processing of chromatic signals (COLOR VISION) from the eye by the VISUAL CORTEX where they are converted into symbolic representations. Color perception involves numerous neurons, and is influenced not only by the distribution of wavelengths from the viewed object, but also by its background color and brightness contrast at its boundary.
Color Vision
Ultrasonography, Doppler, Color
Ultrasonography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image. This type of ultrasonography is well-suited to identifying the location of high-velocity flow (such as in a stenosis) or of mapping the extent of flow in a certain region.
Color Vision Defects
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the ROD OPSINS genes (on X CHROMOSOME and CHROMOSOME 3) that code the photopigments for red, green and blue.
Echocardiography, Doppler, Color
Colorimetry
Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Lighting
Photic Stimulation
Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.
Retinal Cone Photoreceptor Cells
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.
Feathers
Flat keratinous structures found on the skin surface of birds. Feathers are made partly of a hollow shaft fringed with barbs. They constitute the plumage.
Contrast Sensitivity
Psychophysics
Receptor, Melanocortin, Type 1
Butterflies
Anthocyanins
A group of FLAVONOIDS derived from FLAVONOLS, which lack the ketone oxygen at the 4-position. They are glycosylated versions of cyanidin, pelargonidin or delphinidin. The conjugated bonds result in blue, red, and purple colors in flowers of plants.
Photography
Method of making images on a sensitized surface by exposure to light or other radiant energy.
Pattern Recognition, Visual
Retinal Pigments
Photosensitive protein complexes of varied light absorption properties which are expressed in the PHOTORECEPTOR CELLS. They are OPSINS conjugated with VITAMIN A-based chromophores. Chromophores capture photons of light, leading to the activation of opsins and a biochemical cascade that ultimately excites the photoreceptor cells.
Spectrophotometry
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
Food Packaging
Containers, packaging, and packaging materials for processed and raw foods and beverages. It includes packaging intended to be used for storage and also used for preparation of foods such as microwave food containers versus COOKING AND EATING UTENSILS. Packaging materials may be intended for food contact or designated non-contact, for example, shipping containers. FOOD LABELING is also available.
Meat
Food Coloring Agents
Natural or synthetic dyes used as coloring agents in processed foods.
Blood Flow Velocity
Adaptation, Ocular
Agouti Signaling Protein
A secreted protein of approximately 131 amino acids (depending on species) that regulates the synthesis of eumelanin (brown/black) pigments in MELANOCYTES. Agouti protein antagonizes the signaling of MELANOCORTIN RECEPTORS and has wide distribution including ADIPOSE TISSUE; GONADS; and HEART. Its overexpression in agouti mice results in uniform yellow coat color, OBESITY, and metabolic defects similar to type II diabetes in humans.
Melanins
Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.
Sensitivity and Specificity
Tooth Discoloration
Opsins
Attention
Visual Perception
Ultrasonography, Doppler, Pulsed
Dental Materials
Nature
Visual Cortex
Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.
Reproducibility of Results
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Cues
Image Processing, Computer-Assisted
Materials Testing
Cichlids
Bees
Insect members of the superfamily Apoidea, found almost everywhere, particularly on flowers. About 3500 species occur in North America. They differ from most WASPS in that their young are fed honey and pollen rather than animal food.
Visual Pathways
Phenotype
Maxillofacial Prosthesis
Fundus Oculi
Coloring Agents
Tooth, Artificial
Vision, Ocular
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
Visual Fields
Microspectrophotometry
Analytical technique for studying substances present at enzyme concentrations in single cells, in situ, by measuring light absorption. Light from a tungsten strip lamp or xenon arc dispersed by a grating monochromator illuminates the optical system of a microscope. The absorbance of light is measured (in nanometers) by comparing the difference between the image of the sample and a reference image.
Rod Opsins
Tooth Bleaching
The use of a chemical oxidizing agent to whiten TEETH. In some procedures the oxidation process is activated by the use of heat or light.