Sensation and Perception

Question 1

What is the main difference between sensation and perception?

Answer 1

Sensation is the transduction of external stimuli into to the internal environment, while perception is making sense of such stimuli.

Question 2

Making AI robots is a task that has still not been done. Do robots lack the ability to sense or perceive?

Answer 2

perceive

Question 3

Describe the pathway a peripheral sensory neuron takes to transmit information to the brain.

Answer 3

peripheral sensory neuron -> sensory ganglion -> postganglionic neuron in the spinal cord -> thalamus -> specific part of the brain

Question 4

List off a few examples of sensory receptors?

Answer 4

osmoreceptors, nocireceptors, photoreceptors, hair cells, taste receptors, olfactory receptors, thermoreceptors

Question 5

A thermoreceptor would likely eventually send its signal to what part of the cerebral cortex?

Answer 5

parietal lobe

Question 6

Why is perception usually more interesting to study for psychologists than sensation?

Answer 6

it largely depends on experience– two people can sense the same thing and perceive it entirely differently

Question 7

Define what a threshold is in terms of perception.

Answer 7

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

Question 8

What are the three main types of thresholds? What is another name for a threshold?

Answer 8

• the absolute threshold, the threshold of conscious perception, and the main difference threshold
• limen

Question 9

Explain what an absolute threshold is.

Answer 9

the minimum amount of a stimulus that is required to activate a sensory neuron, not necessarily perception

Question 10

Explain what a threshold of conscious perception is.

Answer 10

the minimum amount of a stimulus that is required to be perceived

Question 11

Is it possible to the have a threshold of conscious perception that is lower than the absolute threshold? Explain.

Answer 11

No. Sensation always precedes perception. Therefore, the stimulus must always first reach the absolute threshold before the threshold of conscious perception.

Question 12

Does a stimulus that exceeds the absolute threshold but not the threshold of conscious perception still reach the brain?

Answer 12

Yes- it just does not go to higher order brain structures. It would stop at the thalamus.

Question 13

What is the difference threshold? What is another name for it?

Answer 13

• the minimum change in intensity of a signal required to perceive
• just noticeable difference (jnd)

Question 14

Weber’s law provides more insight into what type of threshold?

Answer 14

the difference threshold

Question 15

To hear a change in pitch of a voice, patient A has a jnd of 0.75%… what would the change need to be if he is listening to sound at 500 Hz?

Answer 15

500 + 0.0075(500) = 3.75, thus 503.75

Question 16

What is signal detection theory used for? What is the main difference between using this theory to study subjects rather than just using external stimuli?

Answer 16

• used to predict when and how a signal will be recognized amidst other sensory information (nosensory information), which affect the ability to perceive
• in signal detection theory, psychological differences, not just external ones, are studied

Question 17

What is a response bias? Can it be studied by signal detection theory?

Answer 17

• tendency for a subject to respond a certain way due to psychological context (nosensory factors) rather than objective external stimuli
• yes

Question 18

If a researcher was studying a subject and produced a signal that was failed to be picked up, would this be a catch or miss trial? Hit or miss? False alarm or correct negative?

Answer 18

• catch trial

- miss

Question 19

Define what adaptation in terms of perception thresholds?

Answer 19

the change (and generally an increase) in a threshold in order to focus on the most relevant stimuli (e.g. getting an apartment near a train can eventually stopping noticing the sounds).

Question 20

What is the outer most area of the eye called?

Answer 20

sclera

Question 21

What is the inner most area of the eye called?

Answer 21

retina

Question 22

What is the job of the retina?

Answer 22

convert incoming photons into electrical signals using photoreceptors

Question 23

What is the front of the eye called?

Answer 23

cornea

Question 24

Describe what accommodation is in terms of the eye?

Answer 24

the contraction/relaxation of the ciliary muscle to change the shape of the lens, allowing for focus on light onto the retina

Question 25

What is the function of the canal of Schlemm?

Answer 25

to drain aqueous humor from the eye

Question 26

What are the layers of the eye from inner to outer?

Answer 26

retina, choroid, sclera

Question 27

True or False. The retina is considered to be part of the central nervous system.

Answer 27

true

Question 28

Describe the basic idea of the duplexity theory of vision.

Answer 28

that there are two types of photoreceptors in the eye: some for light/dark detection and some for color detection

Question 29

What photoreceptors sense color in the eye?

Answer 29

cone cells

Question 30

What photoreceptors sense light/dark in the eye?

Answer 30

rod cells

Question 31

The cones in the eye most strongly detect what three colors?

Answer 31

blue, green, red

Question 32

A high concentration of rhodopsin would be found in which receptor in the retina?

Answer 32

rod cells

Question 33

What part of the retina would have the highest visual acuity? Why?

Answer 33

- fovea | - it has exclusively cone cells, which detect fine differences

Question 34

True or False. The rod and cone cells in the retina connect directly with the optic nerve.

Answer 34

false

Question 35

Rods and cones connect with which type of cell: a) amacrine cells b) horizontal cells c) ganglion cells d) bipolar cells

Answer 35

d

Question 36

What cells makes up the optic nerve? a) amacrine cells b) horizontal cells c) ganglion cells d) bipolar cells

Answer 36

c

Question 37

When light is detected by rhodopsin in rod cells, what happens to the membrane potential?

Answer 37

hyperpolarization

Question 38

The light information travels from the optic nerves in both eyes in what?

Answer 38

optic tracts

Question 39

The temporal visual fields of the eyes on both sides cross at the...

Answer 39

optic chiasm

Question 40

The right visual field goes to what side of the brain?

Answer 40

the left

Question 41

Where do the optic tracts ultimately lead to?

Answer 41

the lateral geniculate nucleus of the thalamus

Question 42

Once sensing of light and color is done, what process do we use to perceive it?

Answer 42

parallel processing

Question 43

What is parallel processing?

Answer 43

the ability to perceive incoming visual signals as color, shape, and motion

Question 44

In neuroscience, parallel processing is called what?

Answer 44

feature detection

Question 45

What cells detect color according to feature detection?

Answer 45

cones

Question 46

What cells detect shape according to feature detection?

Answer 46

parvocellular cells

Question 47

What cells detect motion according to feature detection?

Answer 47

magnocellular cells

Question 48

What is the difference between spatial and temporal resolution?

Answer 48

spatial resolution refers to the size of the pixel (high resolution = small pixel sizes), while temporal resolution refers to how often the pixels are updated (high resolution = updated often)

Question 49

What are the three main divisions of the ear?

Answer 49

the inner, middle, and outer ear

Question 50

What are the three main parts of the outer ear?

Answer 50

the pinna (auricle), external auditory canal, and the tympanic membrane

Question 51

True or False. The tympanic membrane vibrates more frequently as the intensity of the noise increases.

Answer 51

false

Question 52

What are the bones of the middle ear called?

Answer 52

the ossicles

Question 53

What are the three ossicles?

Answer 53

malleus, incus, stapes

Question 54

Which ossicle is in contact with the tympanic membrane?

Answer 54

malleus

Question 55

What structure of the inner ear is the stapes in contact with?

Answer 55

the oval window

Question 56

What is the function of the Eustachian tube? Where is it located?

Answer 56

- equilibrate pressure differences between the ear and nasal cavity - middle ear

Question 57

What are the two matrices of the inner ear?

Answer 57

the bony matrix and the membraneous matrix

Question 58

What substance sits within the bony matrix and bathes the membraneous maxtrix?

Answer 58

perilymph

Question 59

Would you expect there to be more free ions in the perilymph or endolymph?

Answer 59

the endolymph

Question 60

What are the three structures that make up the membraneous matrix?

Answer 60

-cochlea, vestibule, semicircular canals

Question 61

What is the function of the cochlea? What is the main organ that does this?

Answer 61

- convert auditory physical stimuli into electrical stimuli | - organ of Corti

Question 62

The endolymph is a liquid and is essentially incompressible. If this statement is true, how are vibrations sent through the matrix to the organ of Corti?

Answer 62

the round window in the inner ear is flexible and can move in response to vibrations

Question 63

What is the nerve connected to the cochlea called?

Answer 63

vestibulocochlear nerve (or simply the auditory nerve)

Question 64

True or False. The auditory signals are sent directly to higher cerebral cortex structures and do not first pass through the thalamus.

Answer 64

false

Question 65

Explain what it means for the cochlea to be tonotopically organized.

Answer 65

The hairs in the organ or Corti that run continuously throughout the cochlear tail are specific for certain pitches; for instance, ones that are closer to the round window vibrate more quickly and thus correspond to higher pitch sounds

Question 66

What is a kinesthetic sense?

Answer 66

also known as proprioception, it is the ability to sense where your body is and where/how it is moving

Question 67

What does the vestibule do?

Answer 67

senses linear acceleration by using hairs specialized with otoliths

Question 68

What do the semicircular structures do?

Answer 68

sense rotational acceleration by using ampulla

Question 69

How are hairs in the ear different than hairs on your head?

Answer 69

they have sterocilia, specialized for hearing

Question 70

Where does the auditory tract lead signals to after being produced by the organ of Corti?

Answer 70

medial geniculate nucleus of the thalamus (MGN)

Question 71

What are two possible locations where the MGN would send auditory signals to?

Answer 71

- the temporal lobe | - inferior colliculus

Question 72

What is unique about the signals corresponding to the sense of smell compared to other senses?

Answer 72

they do not go to the thalamus

Question 73

While the thalamus organizes incoming sight and hearing signals, the analogous structure for smell is known as the _____ _____.

Answer 73

olfactory bulb

Question 74

What is a pheremone?

Answer 74

any olfactant that causes a change in behavior, used for communication

Question 75

What type of receptors are used for taste?

Answer 75

chemoreceptors

Question 76

The sense of touch is often oversimplified to mean being able to feel an object... what other modalities are there?

Answer 76

temperature, pressure, pain, vibration

Question 77

What are the five main types of somatosensory receptors?

Answer 77

- free nerve endings - Meissner corpuscle - Ruffini endings - Pacinian corpuscle - Merkle discs

Question 78

What are the functions of the five main somatosensory receptors?

Answer 78

- free nerve endings (detect temp/pain) - Meissner corpuscle (detect light touch) - Ruffini endings (detect strech) - Pacinian corpuscle (detect pressure/vibrations) - Merkle discs (detect pressure/texture)

Question 79

In regard to somatosensation, what is the two-point threshold?

Answer 79

the minimum difference between two points of touch to be felt as two distinct stimuli

Question 80

In regard to somatosensation, what is the gate theory of pain?

Answer 80

the theory that pain produced by nociceptors can be masked by converting it to other types of receptors (explains why rubbing an injury makes it feel better)

Question 81

In regard to somatosensation, what does physiological zero mean?

Answer 81

it means all temps are considered cold/hot relative to normal skin temp

Question 82

What is bottom-up (data driven) processing?

Answer 82

using parallel processing to identify an object

Question 83

What is town-down (conceptually driven processing)?

Answer 83

using memory to quickly identify an object

Question 84

When opening up her math textbook to read for the first time, Sally was overwhelmed by the complex equations. However, after a few weeks, when she opened up the book and reread the equations, she found they were easier to grasp. What type of processing is this?

Answer 84

top-down processing

Question 85

Suppose Sally ran into two equations in her math book that looked alike. She initially thought there was a printing error that resulted in the equation being written twice, but after examination, she realized they were slightly different. What type of processing is this?

Answer 85

bottom-up processing

Question 86

What is the ability to use bottom-up and town-down processing simulataneously?

Answer 86

perceptual organization

Question 87

Why is perceptual organization useful?

Answer 87

it allows the individual to understand an idea more clearly

Question 88

What are Gestalt principles?

Answer 88

ways in which the brain fills in gaps to make sense of an object

Question 89

What are some Gestalt principles?

Answer 89

law of proximity, law of similarity, law of subjective contours, law of good continuation, law of closure

Question 90

What law governs all Gestalt principles?

Answer 90

law of Pragnanz

Question 91

What does the law of Pragnanz state?

Answer 91

that all Gestalt principles are simple, regular, and symmetrical