Chapter 6b Flashcards
The distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of gamma rays to the long pulses of radio transmission.
Wavelength
The dimension of color that is determined by the wavelength of light; what we know as the color names, blue, green, and so forth.
Hue
The amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness. This is determined by the wave’s amplitude (height).
Intensity
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.
Retina
The process by which the eye’s lens changes shape to focus near or far objects on the retina.
Accommodation
Retinal receptors that detect black, white, and gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond.
Rods
Retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. These detect fine detail and give rise to color sensations.
Cones
The nerve that carries neural impulses from the eye to the brain.
Optic Nerve
The point at which the optic nerve leaves the eye, creating a “blind’ spot because no receptor cells are located there.
Blind Spot
The central focal point in the retina, around which the eye’s cones cluster.
Fovea
The theory that the retina contains three different color receptors - one most sensitive to red, one to green, one to blue - which, when stimulated in combination, can produce the perception of any color.
Young Helmholtz Trichromatic Theory
The theory that opposing retinal processes (red-green, yellow-blue, 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.
Opponent Process Theory
Nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement.
Feature Detectors
Processing many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions, including vision.
Parallel Processing
An organized whole. Psychologists of this type emphasized our tendency to integrate pieces of information into meaningful wholes.
Gestalt
The organization of the visual field into objects that stand out from their surroundings.
Figure Ground
The perceptual tendency to organize stimuli into coherent groups.
Grouping
The ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance.
Depth Perception
A laboratory device for testing depth perception in infants and young animals.
Visual Cliff
A depth cue; such as retinal disparity, that depends on the use of two eyes.
Binocular Cue
A binocular cue for perceiving depth. By comparing retinal images from the two eyes the brain computes distance - the greater the disparity (difference) between the two objects, the closer the object.
Retinal Disparity
A depth cue; such as interposition or linear perspective, available to either eye alone.
Monocular Cue
An illusion of movement created when two or more adjacent lights blink on and off in quick succession.
Phi Phenomenon
Perceiving objects as unchanging (having consistent color, brightness, shape, and size) even as illumination and retinal images change.
Perceptual Constancy
The ability to adjust to changed sensory input, including an artificially displaced or even inverted visual field.
Perceptual Adaptation
