Module 22 - Vision: Sensory and Perceptual Processing Flashcards
Wavelength
The distance from the peak of one wave to the next
Hue
The dimension of color determined by the wavelength of light
Intensity
The amount of energy in a light/sound wave, which influences what we perceive as brightness or loudness. Determined by amplitude
Cornea
The eye’s clear, protective outer layer, covering the pupil and iris
Pupil
The adjustable opening in the center of the eye through which light enters
Iris
A ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
Lens
The transparent structure behind the pupil that changes shape to help focus images on the retina
Retina
The light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
Accommodation
The process by which the eye’s lens changes shape to focus near or far objects on the retina
Rods
Retinal preceptors that detect black, white, gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond
Cones
Retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations
Blind spot
The point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there
Fovea
The central focal point in the retina, around which the eye’s cones cluster
Young-Helmholtz trichromatic color theory
The theory that the retina contains three different types of color receptors—one most sensitive to red, green, or blue—which, when stimulated in combination, can produce the perception of any color
Opponent-process theory
The theory that opposing retinal processes (red-green, blue-yellow, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
