Topic 3 Perception pt 2

Question 1

true or false: the proximal stimulus is measured on an absolute scale

Answer 1

false: the proximal stimulus is measured on a relative scale. For example, we don’t measure how much light enters the photoreceptors- we instead measure how much light enters the photoreceptors relative to the other photoreceptors

Question 2

what is a blind spot, and what causes it

Answer 2

A blind spot is the area in the retina whereby there are no photoreceptors due to the axons passing over the front of the retina (there is simply no room for the photoreceptors because of the axons)

Question 3

the sensitivity of the visual system depends on the _______

Answer 3

the sensitivity of the visual system depends on the ambient light levels

Question 4

Jack is in a dark room and then turns on the flashlight. In another room, Jill is in a well lit room and turns on the flashlight. Who will experience an increase in firing rate in their visual cortex?

Answer 4

Jack, because he is in the darker room

Question 5

What variable is the Weber fraction?

Answer 5

K

Question 6

higher order neurons have _____ receptive fields

Answer 6

higher order neurons have larger receptive fields and respond to more complex stimuli

Question 7

receptive fields

Answer 7

area of sensory surface to which a neuron responds

Question 8

perceptual resolution and acuity are ____ related to sensory receptive field size

Answer 8

perceptual resolution and acuity are inversely related to sensory receptive field size

Question 9

higher order neurons have _____ receptive fields and ______ acuity

Answer 9

higher order neurons have larger receptive fields and lower acuity

Question 10

respond to more complex stimuli

Answer 10

higher order neuron

Question 11

what happens to the firing rate when light shines on the on center of the ganglion cell receptive field

Answer 11

on center = fires more when there is more light in the center

Question 12

what happens to the firing rate when light shines on the off center of the ganglion cell receptive field

Answer 12

off center = fires below baseline due to inhibitory input

Question 13

what will happen if we shine a light on the entire receptive field of the ganglion cell?

Answer 13

slight increase in firing rate

Question 14

what happens if we shine a light on the surround ?

Answer 14

decrease in firing rate

Question 15

what happens if we shine a light outside the receptive field

Answer 15

no change in baseline firing rate

Question 16

receptive field of a hair cell is based on

Answer 16

frequency of the sound

Question 17

what happens to the sizes of the cones as you get further away from the fovea? what happens to the spacing?

Answer 17

the size of the cones get bigger, and have larger receptive fields, and therefore have lower acuity. The cones are also more spaced apart

Question 18

explain integration of light in retina

Answer 18

photoreceptors feed information to bipolar cells and then the single ganglion cells. A single retinal ganglion cells is receiving input from a large number of photoreceptors. The receptive field for the retinal ganglion cell is equal to the receptive field of all the combined photoreceptors

Question 19

receptive field of a mechanoreceptor

Answer 19

area on the skin

Question 20

Spatial organization (____) of sensory surface is preserved and projected onto the ______

Answer 20

Spatial rganization (topography) of sensory surface is preserved and projected onto the primary sensory cortex

Question 21

cortical magnification

Answer 21

the area in the cortex is proportional to density of sensory receptors and inversely related to the receptive field size

Question 22

tonotopic map relies on

Answer 22

frequency (tone = frequency)

Question 23

topographic map for taste is based on

Answer 23

taste quality (sweet, salty , sour)

Question 24

cortical reorganization

Answer 24

changes in topographical map

Question 25

true or false: lower order sensory neurons are closer to the sensory receptors

Answer 25

true

Question 26

how does processing occur as information travels from lower order neurons to higher order neurons

Answer 26

processing proceeds serially (sequentially), parallel (simultaneously), and is recurrent (loops)

recurrent= arrows are double ended and bidirectional

Question 27

tertiary visual cortex is the same as _____

Answer 27

visual association cortex (MST, LIP)

Question 28

multimodal association cortex

Answer 28

VIP

Question 29

Why is V1 the same as striated cortex?

Answer 29

alternation between left and right eye visual field gives it a stripes pattern

Question 30

blobs

Answer 30

unit of cells in the cortical columns (V1) are interested in colors. Mixed in the orientation process, we are also interested in the color

Question 31

explain the more complex feature detector of length

Answer 31

we have feature detectors for oriented lines of a specific length which have excitation and inhibitory areas.

Question 32

What is the function of having feature detectors for length and orientation

Answer 32

Once you can detect lines at a particular length of a particular orientation, you can combine these detections and eventually make out a shape (can detect angles)

Question 33

What happens if you have bilateral damage to V5?

Answer 33

loss of motion perception and everything looks still and you see things in snippets of images

Question 34

what is the feature detector for where sounds are coming from

Answer 34

superior colliculus: sound helps guide the eye

Question 35

interaural time delay

Answer 35

difference in arrival sound of the 2 ears. Detecting this allows to infer where the sound is coming from

Question 36

we know where sound is coming from based on _______ detectors

Answer 36

coincidence detectors

Question 37

heirarchy in the somatosensory system (primary, secondary, tertiary, multimodal) are found primarly in the ____ lobe

Answer 37

parietal lobe

Question 38

what are more complex feature detectors

Answer 38

in the somatosensory cortex for the hands, there are motion sensitive neurons, orientation sensitive neurons, and direction sensitive neurons