Psych - Chapter 6

retinal disparity

a binocular cue for perceiving depth: by comparing images from the retinas in the two eyes, the brain computes distance - the greater the disparity (distance) between the two images, the closer the object

human factors psychology

a brance of psychology that explores how people and machines interact and how machines and physical environments can be made safe and easy to use

cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

cochlear implant

a device for converting sounds into electrical signals and sitmulating the auditory nerve through electrodes threaded into the cochlea

visual cliff

a laboratory device for testing depth perception in infants and young animals

perceptual set

a mental predisposition to perceive one thing and not another

iris

a ring of muscles tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

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, motivations, and level of fatigue.

pitch

a tone's experienced highness or lowness; depends on frequency

phi phenomenon

an illusion of movement created when two or more adjacent lights blink on and off in quick succession

gestalt

an organized whole. _____ psychologists emphasized our tendency to integrate pieces of information into meaningful wholes

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information

subliminal

below one's absolute threshold for conscious awareness

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

monocular clues

depth cues, such as interposition and linear perspective, available to either eye alone

binocular cues

depth cues, such as retinal disparity, that depend on the use of two eyes

sensory adaptation

diminished sensitivity as a consequence of constant stimulation

sensorineural hearing loss

hearing loss caused by daage to the cochlea's receptor cells of to the auditory nerves; also called nerve deafness

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

place theory

in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated

frequency theory

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

perceptual adaptation

in vision, the ability to adjust to an artificially displaced or even inverted visual field

top-down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations

feature detectors

nerve cells in the brain that respons to specific features of the stimulus, such as shape, angle, or movement

color constancy

perceiving familiar objects as having consistent color, even if changing illumination alters the wavelenths reflected by the object

perceptual constancy

perceiving objects as unchanging (having consistent shapes, size, lightness, and color) even as illumination and retinal images change

cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. the ________ detect fine detail and give rise to clor sensations.

rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond

depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance.

priming

the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response

pupil

the adjustable opening in the center of the eye through which light enters

intensity

the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave's amplitude

fovea

the central focal point in the retina, around which the eye's cones cluster

middle ear

the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the chochlea's oval window

extrasensory perception (ESP)

the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition

hue

the dimension of color that is determined by the wavelength of light: what we know as the color names blue, green, etc.

wavelength

the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic __________ vary from the short blips of cosmic rays to the long pulses of radio transmissions

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

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

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time. we experience the ______ _____ as a just noticeable difference (jnd)

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

optic nerve

the nerve that carries neural impulses from the eye to the brain

frequency

the number of complete wavelengths that pass a point in a given time (for example, per second)

figure-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

blind spot

the point at which the optic nerve leaves the eye, creating a ________ _________ because no receptor cells are located there

sensory interaction

the principle that one sense may influence another, as when the smell of food influences its taste

Weber's law

the principle that, to be perceived as different, two stimuli must differ by by a constant minimum percentage (rather than a constant amount)

sensation

the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

accommodation

the process by which the eye's lens changes shape to focus near or far objects on the retina

perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

parallel processing

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.

vestibular sense

the sense of body movement and position, including the sense of balance

audition

the sense or act of hearing

parapsychology

the study of paranormal phenomena, including ESP and psychokinesis

psychophysics

the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them

kinesthesis

the system for sensing the position and movement of individual body parts

opponent-process 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

Young-Helmholtz trichromatic (three-color) theory

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

gate-control theory

the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain. the "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain

lens

the transparent structure behind the pupil that changes shape to help focus images on the retina