sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
perception
the process of organizing and interpreting sensory information, allowing us to recognize meaningful objects/events
bottom-up processing
analysis beginning with sensory receptors and works up to brain's integration of sensory information
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
psychophysics
the study of relationships between physical characteristics of stimuli, such as their intensity, and our psychological experience of them
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time
signal detection theory
a theory predicting how and when we detect the presence of a faint stimulus(signal) amid background stimulation (noise); assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, an
subliminal
below one's absolute threshold for conscious awareness
priming
the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference
weber's law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
sensory adaption
diminished sensitivity as a consequence of constant stimulation
transduction
conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret
wavelength(2)
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from short cosmic rays to long pulses of radio transmission
hue(2)
the dimension of color that is determined by the wavelength of light; colors such as blue, green, etc
intensity(2)
the amount of energy in a light or sound wave, which we perceive as brightness or loudness; determined by the wave's amplitude
pupil(2)
the adjustable opening in the center of the eye through which light enters
iris(2)
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(2)
the transparent structure behind the pupil that changes shape to help focus images on the retina
retina(2)
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(2)
the process by which the eye's lens changes shape to focus near or far objects on the retina
rods(2)
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
cones(2)
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. cones detect fine detail and perceive color
optic nerve(2)
the nerve that carries neural impulses from the eye to the brain
blind spot(2)
the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there
fovea(2)
the central focal point int the retina, around which the eye's cones cluster
feature detectors(3)
nerve cells in the brain that respond to specific stimulus features , such as shape, angle or movement
parallel processing(3)
the processing of many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision. Contrasts with the step-by-step(serial) processing of most computers and of conscious problem solving
Young-Helmholtz trichromatic (three color) theory(3)
the theory that the retina contains three different color receptors - one most sensitive to red, to green and to blue - which, when stimulated in combination, can produce the perception of any color
opponent process theory(3)
the theory that opposing retinal processes (ex.red-green) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
audition(4)
the sense or act of hearing
frequency(4)
the number of complete wavelengths that pass a point in a given time
pitch(4)
a tone's experienced highness or lowness; depends on frequency
middle ear(4)
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window
cochlea(4)
a coiled, bony fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
inner ear(4)
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs
place theory(4)
in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated
frequency theory(4)
in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch
conduction hearing loss(4)
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
sensorineural hearing loss(4)
hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness
cochlear implant(4)
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
kinesthesis(5)
the system for sensing the position and movement of the individual body parts
vestibular sense(5)
the sense of body movement and position, including the sense of balance
gate-control theory(5)
the theory that the spinal cord contains a neurological gate that blocks pain signals or allows them to pass to the brain; the gate is opened by the activity of pain signals traveling up small nerve fibers and is closed by larger fiber activity or info co
sensory interaction(5)
the principle that one sense may influence another; ex: smell influences taste
gestalt(5)
an organized whole; gestalt psychologists emphasize our tendency to integrate pieces of info into meaningful wholes
figure ground(5)
the organization of the visual field into objects that stand out from their surroundings
grouping(5)
perceptual tendency to organize stimuli into groups
depth perception(6)
the ability to see objects in 3D although the images striking the retina are 2D; allows us to judge distance
visual cliff(6)
a laboratory device for testing depth perception in infants/young animals
binocular cues(6)
depth cues, such as retinal disparity, that depend on the use of two eyes
retinal disparity(6)
a binocular cue for perceiving depth; by comparing two images from the retinas in the two eyes, brain computes difference or the greater disparity between two images, the closer the object
monocular cues(6)
depth cues, such as interposition and linear perspective, available to either eye alone
phi phenomenon(6)
an illusion of movement created when two or more adjacent lights blink on and off in quick succession
perceptual constancy(6)
perceiving objects as unchanging(having consistent shapes, size, lightness, and color) even as illumination and retinal images change
color constancy(6)
perceiving objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object
perceptual adaptation
in vision, the ability to adjust to an artificially displaced or even inverted visual field
perceptual set
a mental predisposition to perceive one thing and not another