Biomaterial Database

Detection and discrimination of moving stimuli: the effects of color, luminance, and eccentricity. 1994

A B Metha, and A J Vingrys, and D R Badcock

Department of Optometry, University of Melbourne, Parkville, Victoria, Australia.

Psychophysical detection and direction discrimination thresholds for 1c/o, 1-Hz Gabors are plotted in a Weberian long-middle-wavelength-sensitive cone contrast plane. The shape of these threshold contours suggests linear cone contributions to additive (delta L/Lb + delta M/Mb) and opponent (delta L/Lb - delta M/Mb) postreceptoral mechanisms. The opponent mechanism dominates thresholds at the fovea, but sensitivity decreases rapidly with eccentricity in comparison with the additive mechanism. Cone contributions to the mechanisms vary in a small and nonsystematic manner across the retina. The experiments show that the additive mechanism is directionally sensitive at detection threshold. At all eccentricities studied (0-24 degrees), 0.3-log-unit suprathreshold contrasts are necessary for the opponent mechanism to signal direction of motion.

UI	MeSH Term	Description	Entries
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D009039	Motion Perception	The real or apparent movement of objects through the visual field.	Movement Perception,Perception, Motion,Perception, Movement
D011601	Psychophysics	The science dealing with the correlation of the physical characteristics of a stimulus, e.g., frequency or intensity, with the response to the stimulus, in order to assess the psychologic factors involved in the relationship.	Psychophysic
D003118	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 Perceptions,Perception, Color,Perceptions, Color
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012684	Sensory Thresholds	The minimum amount of stimulus energy necessary to elicit a sensory response.	Sensory Threshold,Threshold, Sensory,Thresholds, Sensory
D017949	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.	Cone Photoreceptors,Cones (Retina),Cone Photoreceptor Cells,Photoreceptors, Cone,Retinal Cone,Retinal Cone Cells,Retinal Cone Photoreceptors,Cell, Cone Photoreceptor,Cell, Retinal Cone,Cells, Cone Photoreceptor,Cells, Retinal Cone,Cone (Retina),Cone Cell, Retinal,Cone Cells, Retinal,Cone Photoreceptor,Cone Photoreceptor Cell,Cone Photoreceptor, Retinal,Cone Photoreceptors, Retinal,Cone, Retinal,Cones, Retinal,Photoreceptor Cell, Cone,Photoreceptor Cells, Cone,Photoreceptor, Cone,Photoreceptor, Retinal Cone,Photoreceptors, Retinal Cone,Retinal Cone Cell,Retinal Cone Photoreceptor,Retinal Cones