2 Sensation and Perception

Question 1

sensation

Answer 1

transduction
conversion of physical, electromagnetic, auditory, and other information from internal/external environment to electrical signals in nervous system

Question 2

perception

Answer 2

processing of sensory information to make sense of its significance

Question 3

sensory receptors

Answer 3

neurons that respond to stimuli and trigger electrical signals

Question 4

distal stimuli

Answer 4

originate outside body (ex. photons)

Question 5

proximal stimuli

Answer 5

directly interact with and affect sensory receptors

inform observer about presence of distal stimuli

Question 6

ganglia

Answer 6

collections of neuron cell bodies found outside the central nervous system

Question 7

stimuli

Answer 7

travel to receptors –> ganglia (via transduction) –> electrochemical energy along neural pathways –> various projection areas in brain for further analysis (perception)

Question 8

photoreceptors

Answer 8

sight (electromagnetic waves in visible spectrum)

Question 9

hair cells

Answer 9

respond to movement of inner ear structures’ fluid

hearing, rotational and linear acceleration

Question 10

nociceptors

Answer 10

respond to painful/noxious stimuli

somatosensation

Question 11

thermoreceptors

Answer 11

respond to changes in temperature

thermosensation

Question 12

osmoreceptors

Answer 12

respond to osmolarity of blood

water homeostasis

Question 13

olfactory receptors

Answer 13

respond to volatile compounds

smell

Question 14

taste receptors

Answer 14

respond to dissolved

taste

Question 15

threshold

Answer 15

minimum amount of stimulus that renders a difference in perception

“limina”

good example of perception

Question 16

absolute threshold

Answer 16

minimum of stimulus energy needed to activate and sensory system

sensation NOT perception

Question 17

subliminal perception

Answer 17

perception of a stimulus below a given a threshold

“threshold of conscious perception”

Question 18

difference threshold

Answer 18

“just-noticeable difference”

minimum difference in magnitude between 2 stimuli before one can perceive the difference

Question 19

Weber’s Law

Answer 19

there is a constant ration between the change in stimulus magnitude needed to produce JND and the magnitude of the original stimulus

higher magnitude of stimulus needs larger difference to produce JND

Question 20

signal detection theory

Answer 20

focuses on the changes in our perception of the same stimuli depending on both internal (psychological) and external (environmental) context

Question 21

response bias

Answer 21

tendency of subjects to systematically respond to a stimulus in a certain way due to nonsensory factors

Question 22

adaptation

Answer 22

our detection of a stimulus can change over time
both physiological (sensory) and psychological (perceptual)

Question 23

rods

Answer 23

functional; light & dark

Question 24

cones

Answer 24

bright light; 3 wavelengths (blue(short), green, red(long))

Question 25

parallel processing

Answer 25

visual processing

simultaneously analyze and combine info (color and shape and motion)

compared to memories for what is being viewed (feature detection)

Question 26

hearing and vestibular sense

Answer 26

complex

hair cells –> stereocilia sway, open ion channels

Question 27

place theory

Answer 27

location of hair cell on basilar membrane determines perception of pitch

Question 28

olfactory nerves

Answer 28

upper part of nasal cavity

chemical stimuli bind to their respective chemoreceptors, cause signal through olfactory pathway

Question 29

taste

Answer 29

chemoreceptors sensitive to dissolved compounds

sweet, salty, bitter, sweet, umami
tastebuds “papillae” –> brainstem

Question 30

somatosensation

Answer 30

pressure, vibration, pain, temperature receptors

Question 31

transduction

Answer 31

somatosensory cortex (parietal lobe)

Question 32

two-point threshold

Answer 32

minimum distance necessary between two points of stimulation to be distinguished as two stimuli

Question 33

physiological zero

Answer 33

86 to 97ºF is normal temperature of skin – all other heat/cold judged relative to this

Question 34

gate theory of pain

Answer 34

“gating” mechanism that can turn pain signals on/off

spinal cord can preferentially forward signals to other modalities
reduce sensation of pain

Question 35

kinesthetic sense

Answer 35

where one’s body is in space

Question 36

bottom-up processing (data driven)

Answer 36

object recognition by parallel processing and feature detection

Question 37

top-down processing (conceptually driven)

Answer 37

memories/expectations recognize whole object then break down components based on expectations

Question 38

perceptual organization

Answer 38

tandem use of top-down and bottom-up to create a hole picture of an object

Question 39

depth perception

Answer 39

monocular/binocular cues

Question 40

form

Answer 40

parallel processing and feature detection

Question 41

constancy

Answer 41

perceive certain characteristics of objects to stay the same, despite differences in environment

Question 42

Gestalt principles

Answer 42

ways for brain to infer missing parts of a picture when incomplete

• proximity
• similarity
• good continuation
• subjective contours
• closure

Question 43

law if prägnanz

Answer 43

perceptual organization will always be as regular, symmetrical, and simple as possible