Chapter 2: Sensation and Perception

Question 1

What is transduction?

Answer 1

conversion of physical, electromagnetic, auditory information from internal or external environment to electrical signals in the nervous system (sensory information)

Question 2

What is perception?

Answer 2

Processing sensory information to make sence of its significance

Question 3

What are sensory receptors?

Answer 3

neurons that respond to stimuli and trigger electrical signals

Question 4

Distal Stimuli

Answer 4

stimuli that originate from outside of the body

Question 5

Proximal Stimuli

Answer 5

interact/affect sensory receptors, and inform the observer about the presence of distal stimuli

Question 6

Ganglia

Answer 6

neuron cell bodies round outside central nervous system

receptors receive stimuli and transmit information to the nervous system through the ganglia

Question 7

Photoreceptors

Answer 7

respond to electromagnetic waves in visible light spectrum (sight)

Question 8

Hair Cells

Answer 8

respond to movement of fluid in inner ear structure (hearing)

Question 9

Nociceptors

Answer 9

respond to pain or noxious stimuli (somatosensation)

Question 10

Thermoreceptors

Answer 10

respond to changes in temperature

Question 11

Osmoreceptors

Answer 11

respond to osmolarity (water homeostasis)

Question 12

Olfactory Receptors

Answer 12

Respond to volatile compounds (smell)

Question 13

Taste Receptors

Answer 13

respond to dissolved compounds (taste)

Question 14

Threshold

Answer 14

The minimum amount of a stimulus that renders a difference in perception

Question 15

What is absolute threshold?

Answer 15

• minimum of stimulus energy needed to activate a sensory system
• threshold in SENSATION

Question 16

What is the threshold of Conscious Perception?

Answer 16

• Threshold by which a stimuli not only reaches the CNS, but reaches high order brain regions that control attention and consciousness

Question 17

What is the difference threshold ?

Answer 17

minimum difference in magnitude between two stimuli before one can perceive a difference

Question 18

Describe Weber’s Law

Answer 18

There is a constant ratio between change in stimulus and and the original magnitude of the stimulus

Question 19

Signal Detection Theory

Answer 19

changes of perception of the same stimuli depending on internal and external context

Question 20

Response Bias

Answer 20

Tendency to respond to a stimulus in a particular way

Question 21

Sclera

Answer 21

White of the eye, covers most of the exposed region of the eye

Question 22

Choroidal and retinal vessels

Answer 22

provide nutrients to the eye

Question 23

Retina

Answer 23

innermost layer of the eye, contains photoreceptors

converts incoming photons of light to electrical signals

Question 24

Cornea

Answer 24

Gathers and focuses incoming light

Question 25

The front of the eye is divided into the :

Answer 25

anterior and posterior chamber

Question 26

Which two muscles make up the pupil?

Answer 26

Dilator and constrictor pupillae

Question 27

ciliary body

Answer 27

produces aqueous humor that bathes the front part of the eye

Question 28

canal of Schlemm

Answer 28

drains aqueous humor

Question 29

lens

Answer 29

helps control incoming light

Question 30

What is accommodation?

Answer 30

Change of the shape of the lens

Question 31

The retina is made up of cones and rods. What is the function of the rods?

Answer 31

Rods only contain rhodamine, so they only allow sensation of light and dark; allow for night vision

Question 32

The retina is made up of cones and rods. What is the function of the cones?

Answer 32

Used for color vision and to sense fine detail

Question 33

What occurs at the optic chiasm?

Answer 33

fibers from nasal half of each retina crosses paths

Question 34

What is parallel processing?

Answer 34

the ability to simultaneously analyze and combine information regarding shape, color and motion (ex: recognizing a moving car)

Question 35

What cells recognize shape?

Answer 35

Parvocellular

Question 36

What cells recognize motion?

Answer 36

magnocellular

Question 37

Describe the functional of the outer membrane?

Answer 37

The pinna directs sound to the external auditory canal. The canal directs sounds to the eardrum.

Question 38

What are the roles of the ossicles in the middle ear?

Answer 38

Transmit and amplify the vibrations from the tympanic membrane to the inner ear.

Question 39

Where is the organ of Corti located?

Answer 39

cochlea

Question 40

What is the role of the organ of Corti?

Answer 40

convert physical stimulus into electrical signal which is carried to the CNS by auditory nerves

Question 41

What is the role of the vestibule

Answer 41

contains the utricle and saccule, which is important in determining one's orientation in 3D space (sensitive to linear acceleration)

Question 42

What is the semicircular canals sensitive to?

Answer 42

rotational acceleration

Question 43

How does sound information pass from the brainstem to the thalamus?

Answer 43

medial geniculate nucleus

Question 44

What is the role of the auditory cortex?

Answer 44

sound processing

Question 45

Describe the role of hair cells?

Answer 45

Hair cells have stereocilia on their surface that sway when vibrations hit the basilar membrane, causing ion channels to open

Question 46

What is place theory?

Answer 46

The location of hair cells on the basilar membrane determines the perception of pitch when the hair is vibrated

Question 47

What are pheromones?

Answer 47

smells that carry roles in animals social, foraging and sexual behavior

Question 48

Pacinian corpuscles

Answer 48

respond to deep pressure and vibration

Question 49

Meissner corpuscles

Answer 49

respond to light touch

Question 50

Merkel cells

Answer 50

respond to deep pressure and texture

Question 51

Ruffini endings

Answer 51

respond to stretch

Question 52

Free nerve endings

Answer 52

respond to pain and temperature

Question 53

What are the four modalities of somatosensation?

Answer 53

pain, temperature, pressure, vibration

Question 54

Two point threshold

Answer 54

minimum distance needed between two points of stimulation on the skin such that the points will be felt as two distinct stimuli

Question 55

physiological zero

Answer 55

skin temperature

Question 56

What is the role of nocireceptors?

Answer 56

pain perception

Question 57

What is kinesthetic sense?

Answer 57

ability to tell where one's body is in space

Question 58

Bottom-up processing

Answer 58

refers to object recognition by parallel processing and feature detection (data driven)

Question 59

Top-down processing

Answer 59

driven by memories and expectations (conceptually driven)

Question 60

What is perceptual organization?

Answer 60

the ability to use top down and bottom up organization in order to come up with a complete image or idea

Question 61

What is depth perception?

Answer 61

only rely on monocular or binocular cues (one or both eyes)

Question 62

What are Gestalt's Principles?

Answer 62

The idea that there are ways that the brain infers missing pieces of information

Question 63

Law of proximity

Answer 63

Objects near each other tend to be perceived as a unit

Question 64

Law of similarity

Answer 64

objects similar to each other tend to be grouped

Question 65

Law of good continuation

Answer 65

elements that follow the same pathway tend to be grouped

Question 66

Subjective Contours

Answer 66

perceiving contours, and therefore shapes that are not actually present

Question 67

Law of Closure

Answer 67

When space is enclosed in a contour, it tends to be perceived as a complete figure

Question 68

Law of Pragnanz

Answer 68

Perceptual organization will always be regular, simple and geometric