Chapter 4A Vocab

Question 1

sensation

Answer 1

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

Question 2

perception

Answer 2

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

Question 3

bottom-up processing

Answer 3

analysis that begins with the sensory receptors and works up to the brain’s integration of sensory info.

Question 4

top-down processing

Answer 4

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

Question 5

selective attention

Answer 5

the focusing of conscious awareness on a particular stimulus

Question 6

inattentional blindness

Answer 6

failing to see visible objects when our attention is directed elsewhere

Question 7

change blindness

Answer 7

failing to notice changes in the environment

Question 8

psychophysics

Answer 8

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

Question 9

absolute threshold

Answer 9

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

Question 10

signal detection theory

Answer 10

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.

Question 11

subliminal

Answer 11

below one’s absolute treshold for conscious awareness

Question 12

difference threshold

Answer 12

the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (jnd). (p. 122)

Question 13

Weber’s Law

Answer 13

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

Question 14

sensory adaptation

Answer 14

diminished sensitivity as a consequence of constant stimulation

Question 15

transduction

Answer 15

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.

Question 16

wavelength

Answer 16

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

Question 17

hue

Answer 17

he dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth

Question 18

middle ear

Answer 18

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

Question 19

inner ear

Answer 19

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

Question 20

frequency theory

Answer 20

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.

Question 21

sensioromotor hearing loss

Answer 21

hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; also called nerve deafness.

Question 22

kinesthesis

Answer 22

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

Question 23

gate control theory

Answer 23

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.

Question 24

intensity

Answer 24

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

Question 25

pupil

Answer 25

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

Question 26

iris

Answer 26

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

Question 27

lens

Answer 27

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

Question 28

retina

Answer 28

the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual info.

Question 29

rods

Answer 29

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

Question 30

cones

Answer 30

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.

Question 31

optic nerve

Answer 31

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

Question 32

blind spot

Answer 32

the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there

Question 33

fovea

Answer 33

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

Question 34

feature detectors

Answer 34

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

Question 35

parallel processing

Answer 35

the processing of many aspects of a problem simultaneously; the brain’s natural mode of info. processing for many functions, including vision. contrasts with the step-by-step (serial) processin gof most computers and of conscious problem solving

Question 36

three-color theory

Answer 36

3 receptors in the retina that are responsible for the perception of color

Question 37

opponent process theory

Answer 37

theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. i.e. some cells are stimulated by green and inhibited by red; othrs are stimulated by red and others are inhibited by green

Question 38

audition

Answer 38

the sense or act of hearing

Question 39

frequency

Answer 39

the number of complete wavelengths that pass a point in a given time (i.e. per second)

Question 40

pitch

Answer 40

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

Question 41

cochlea

Answer 41

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

Question 42

place theory

Answer 42

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

Question 43

conduction hearing loss

Answer 43

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

Question 44

cochlear implant

Answer 44

a deevice for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Question 45

vestibular sense

Answer 45

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

Question 46

sensory interaction

Answer 46

principle that one sense may influence another, as whn the smell of food influnces its taste