module 18 vision, sensory, & perceptual processing Flashcards
wavelength
the distance from the peak of the one light wave or sound wave to the peak of the next. Electromagnetic wavelengths vary from short gamma waves to the long pulses of ratio transmission
hue
the dimension of color that is determined by the wavelength of light; what we know as the color names blue and so forth
intensity
the amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness. intensity is determined by the amplitude (height)
retina
the light-sensitive back inner surface of the eye, containing the receptor rods & cones plus layers of neurons that begin the processing of visual information
accommodation
(1) in developmental psychology adapting our current schemas (understandings) to incorporate new information (2) in sensation & perception, the process by which the eye’s lens changes shape to focus on near or far objects on the retina
rods
retinal receptors that detect black, white, and are sensitive to movement. Rods are necessary for peripheral & twilight vision when cones don’t respond
cones
retinal receptors that are concentrated near the center of the retina & that function in daylight or in well-lit conditions. Cones detect fine detail & give rise to color sensations
optic nerve
the nerve that carries neural impulses from the eye to the brain
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 control focal point in the retina, around which the eye’s cones cluster
young helmholtz trichromatic ( 3 color theory)
the theory is that the retina contains 3 different types of color receptors, one most sensitive to red, one most sensitive to gree, and one to blue, which when stimulated in combination, can produce the perception of any color
opponent process theory
the theory that opposing retinal processes (red, gree, blue, yellow, black, white) enable color vision. For ex. some cells are stimulated by gree & inhibited by red; other stimulated by red and inhibited by gree
feature detectors
nerve cells in the brain’s visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement
parallel processing
processing multiple aspects of a stimulus or problem simultaneously
gestalt
an organized whole, gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes
feature ground
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground)
grouping
the perceptual tendency to organize stimuli into coherent groups
depth perception
the ability to seee objects in 3 dimensions, although the images that strike the retina are 2 dimensional; allows us to judge distance
visual cliff
a laboratory device for testing depth perception in infants & young animals
binocular cue
a depth cue, such as retinal disparity, that depends on the use of two eyes
retinal disparity
a binocular for perceiving depth by comparing retinal images from the two eyes, the brain computes distance, the greater the (difference) between the 2 images, the closer the object
monocular cues
a depth cue, such as interposition or linear perspective, available to the other eye alone
phi phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession
perceptual constancy
perceiving objects as unchanging (having consistent color, brightness, shape, and size) even as illumination and retinal images change
