Macmillan chapter 6

accomodation

1. in developmental psychology, adapting our current understandings (schemas) to incorporate new information. 2. in sensation and perception, the process by which the eye's lens changes shape to focus near or far objects on the retina

monocular cues

Depth cues, such as interposition and linear persepective, available to either eye alone

retinal disparity

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

cochlea

a coiled, bony, fluid filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses

cochlear implant

a device for converting sounds into electrical signals and stimulating 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

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, and alertness

pitch

a tone's experienced highness or lowness, depends on the frequency

gestalt

an organized whole. Gestalt 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, transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret

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 damage to the cochlea's receptor cells or 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 impules traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

perceptual adaptaion

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

top-down processing

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

feature detectors

nerve celss in the brain that respond 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 wavelengths reflected by other objects

perceptual constancy

perceiving objects as unchanging( having consistent color, brightness, shape, and size) 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 cones detect fine detail and give rise to color sensations

rods

retinal receptors that detect black, white, and gray; neccessary 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

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 cochlea's oval window

ESP

the controversial claim that perception can occur apart from sensory input; telepathy

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 wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission

embodied cognition

the influence of bodily sensations, gestures, and other states on cognitive preferences and judgements

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 difference threshold as a just noticeable difference or JND

absolute threshold

the minimum stimulation needed to detect a particular stimuluss 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 "blind" spot because no receptor cells are located there

sensory interaction

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

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)

sensation

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

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 sens

the sense of body movement and position, including balance

audition

the sense or act of hearing

parapsychology

the stud of paranormal phenomena, like esp

kinethesis

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.

Young-Helmholtz Trichromatic (three-color) theory

the theory that the retina contains three diferent 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 nuerological gate that blocks pain signals or allows them to pass to the brain. The "gate" is opened by the acttvity of pain signals traveling up small nere fibers and is closed by activity in larger fibers or by information coming from the brain