4.1 We Experience Our World Through Sensation

Question 1

hertz

Answer 1

vibrations per second

Question 2

Psychophysics

Answer 2

the branch of psychology that studies the effects of physical stimuli on sensory perceptions and mental states

Question 3

Gustav Fechner (1801–1887)

Answer 3

he was a German psychologist who founded the field of psychophysics

Question 4

absolute threshold

Answer 4

(of a sensation) is defined as the intensity of a stimulus that allows an organism to just barely detect it

Question 5

Signal detection analysis

Answer 5

a technique used to determine the ability of the perceiver to separate true signals from background noise

Question 6

hit

Answer 6

occurs when you, as the listener, correctly say “yes” when there is a sound

Question 7

false alarm

Answer 7

occurs when respond “yes” to no signal

Question 8

miss

Answer 8

occurs when you say “no” when there is a signal

Question 9

correct rejection

Answer 9

occurs when you say “no” and there was no signal

Question 10

sensitivity

Answer 10

refers to the true ability of the individual to detect the presence or absence of signals

Question 11

response bias

Answer 11

refers to a behavioral tendency to respond “yes” to the trials, which is independent of sensitivity

Question 12

difference threshold

Answer 12

(or just noticeable difference [JND]), refers to the change in a stimulus that can just barely be detected by the organism

Question 13

German physiologist Ernst Weber (1795– 1878)

Answer 13

he made an important discovery about the JND—namely, that the ability to detect differences depends not so much on the size of the difference but on the size of the difference in relationship to the absolute size of the stimulus

Question 14

Weber’s law

Answer 14

maintains that the just noticeable difference of a stimulus is a constant proportion of the original intensity of the stimulus

Question 15

blindsight

Answer 15

a condition in which people are unable to consciously report on visual stimuli but nevertheless are able to accurately answer questions about what they are seeing

Question 16

subliminal advertising

Answer 16

Research has found that stimuli can influence behavior even when they are presented below the absolute threshold (i.e., subliminally). The effectiveness of subliminal advertising, however, has not been shown to be of large magnitude