Sensation and Perception

Question 1

habituation

Answer 1

decreasing responsiveness with repeated stimulation. As infants gain familiarity with repeated exposure to a stimulus, their interest wanes and they look away sooner

Question 2

assimilation

Answer 2

interpreting our new experiences in terms of our existing schemas

Question 3

accommodation

Answer 3

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

Question 4

sensation

Answer 4

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

Question 5

perception

Answer 5

the process by which our brain organizes and interprets sensory information, enabling us to recognize objects and events as meaningful

Question 6

bottom-up processing

Answer 6

information processing that begins with the sensory receptors and works up to the brain’s integration of sensory information

Question 7

top-down processing

Answer 7

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

Question 8

absolute threshold

Answer 8

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

Question 9

signal detection theory

Answer 9

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 10

priming

Answer 10

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

Question 11

difference threshold

Answer 11

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)

Question 12

Weber’s law

Answer 12

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

Question 13

sensory adaptation

Answer 13

diminished sensitivity as a consequence of constant stimulation

Question 14

transduction

Answer 14

conversion of one form of energy into another. In sensation, the transforming of physical energy, such as sights, sounds, and smells, into neural impulses the brain can interpret

Question 15

wavelength

Answer 15

the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short gamma waves to the long pulses of radio transmission

Question 16

hue

Answer 16

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

Question 17

intensity

Answer 17

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 wave’s amplitude (height)

Question 18

pupil

Answer 18

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

Question 19

iris

Answer 19

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 20

lens

Answer 20

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

Question 21

retina

Answer 21

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

Question 22

fovea

Answer 22

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

Question 23

rod

Answer 23

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

Question 24

cones

Answer 24

retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations

Question 25

blind spot

Answer 25

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

Question 26

optic nerve

Answer 26

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

Question 27

parallel processing

Answer 27

processing multiple aspects of a stimulus or problem simultaneously

Question 28

opponent-process theory

Answer 28

the theory that opposing retinal processes (red-green, blue-yellow, 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

Question 29

selective attention

Answer 29

focusing conscious awareness on a particular stimulus

Question 30

inattentional blindness

Answer 30

failing to see visible objects when our attention is directed elsewhere

Question 31

gestalt

Answer 31

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

Question 32

figure ground relationship

Answer 32

the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground)

Question 33

depth perception

Answer 33

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

Question 34

visual cliff

Answer 34

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

Question 35

binocular cues

Answer 35

a depth cue, such as retinal disparity, that depends on the use of two eyes

Question 36

monocular cues

Answer 36

a depth cue, such as interposition or linear perspective, available to either eye alone

Question 37

phi phenomenon

Answer 37

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

Question 38

perceptual constancies

Answer 38

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

Question 39

stages of learning: acquisition

Answer 39

in classical conditioning, the initial stage, when one links a neutral stimulus and an unconditioned stimulus so that the neutral stimulus begins triggering the conditioned response. In operant conditioning, the strengthening of a reinforced response

Question 40

stages of learning: extinction

Answer 40

in classical conditioning, the diminishing of a conditioned response when an unconditioned stimulus does not follow a conditioned stimulus. (In operant conditioning, when a response is no longer reinforced.)

Question 41

stages of learning: spontaneous recovery

Answer 41

the reappearance, after a pause, of a weakened conditioned response

Question 42

generaliztion

Answer 42

(also called stimulus generalization) in classical conditioning, the tendency, once a response has been conditioned, for stimuli similar to the conditioned stimulus to elicit similar responses. (In operant conditioning, when responses learned in one situation occur in other, similar situations.)

Question 43

discrimination

Answer 43

(1) in classical conditioning, the learned ability to distinguish between a conditioned stimulus and other stimuli that have not been associated with a conditioned stimulus. (In operant conditioning, the ability to distinguish responses that are reinforced from similar responses that are not reinforced.) (2) in social psychology, unjustifiable negative behavior toward a group or its members

Question 44

operant conditioning

Answer 44

a type of learning in which a behavior becomes more likely to recur if followed by a reinforcer or less likely to recur if followed by a punisher

Question 45

observational learning

Answer 45

learning by observing others

Question 46

retinal ganglion cells

Answer 46

bridging neurons that connect the retinal input to the visual processing centers within the central nervous system.

Question 47

visual acuity

Answer 47

the ability of the visual system to recognize detail at various distances.

Question 48

relative size

Answer 48

the depth cue in which we perceive distance based on the comparison of sizes between objects. It is the idea that when two or more objects are similar, we assume that the smaller one is farther away.

Question 49

relative height

Answer 49

concept used in visual and artistic perspective where distant objects are seen or portrayed as being smaller and higher in relation to items that are closer. This phenomenon can be seen when looking at a landscape and seeing that distant objects - trees, rocks, animals, etc.

Question 50

linear perspective

Answer 50

a type of depth prompt that the human eye perceives when viewing two parallel lines that appear to meet at a distance

Question 51

size constancy

Answer 51

the ability to perceive an object as being the same size despite the fact that the size of its retinal image changes depending on its distance from the observer. It is a type of perceptual constancy.