Motion Perception

Question 1

Changes in ____ can lead to perception of motion

Answer 1

Spatial distribution of light, over time

Question 2

Motion is processed along a specialized visual pathways, ______

Answer 2

The dorsal processing stream, can use for dx of neural problems

Question 3

When spatially separated lights sequentially flashed with an appropriate interval between flashes, a sense of motion is elicited, called as

Answer 3

Stroboscopic motion or phi phenomenon

Question 4

What uses stroboscopic motion

Answer 4

Movies, television, and computer monitors

Question 5

Frames of movies

Answer 5

Presented at a temporal rate that creates the illusion of smooth motion

Question 6

Motion pictures generally present ____ diff images per second

Answer 6

24

Question 7

Each image of a motion picture is displayed three consecutive times, for a total of ____ presentations per second

Answer 7

72

Question 8

The movie would slicker if the presentation rate is ____ the CFFF

Answer 8

Below

Question 9

As sinusoidal grating is phase shifted over time, to produce a grating that appears to drift of move in a given direction. These stimuli which consist of linear exchange of light or dark, are referred to as

Answer 9

First order stimuli for motion

Question 10

Both stroboscopic stimuli and sine wave gratings are used to study ____ processing

Answer 10

Local motion

Question 11

A bright stimulus that moves across he visual field, the stimulus sequentially _____ the receptive fields of visual neuron in its path

Answer 11

Activates

Question 12

Neurons that respond at differnt latencies

Answer 12

When the stimulus us moving at the proper speed, the slower neurons, which are stimulated first, respond at the same point in time as the faster neurons, which are stimulated later. If these responses are added together, the resulting signal could encode stimulus speed and direction. Neurons capable of encoding certain aspects of motion have been found in the retina

Question 13

What does the latenices of the two differnt neurons from0-20 degrees tell us

Answer 13

By the time a neuron has been excited, the second one has already been excited but in a differnt location. This gives us the speed and location of the stimulation

Question 14

More complex first order stimuli that require the integration of motion cues across a wide expanse of visual space cen be presented with

Answer 14

Random dot kinematograms

-humans do remarkably well on this task, manifesting coherence threshold close to 1%

Question 15

Defined as the smalles percent coherence that results in the perception of motion in a defines direction

Answer 15

Coherence threshold

Question 16

What is the coherent threshold for humans

Answer 16

1%

Question 17

The minimum distance dots must move in a given direction to elicit the perception of motion

Answer 17

Minimum displacement threshold (Dmin)

Question 18

The max distaance the dots can move and still elicit motion perception

Answer 18

Maximum displacement threshold (Dmax)

Question 19

Random dot kinematogram is more complicated than stroboscopic and sine wave stimuli. More complicated because the visual system must integrate information from many dots over a broad expanse of the retina involving higher level cortical motion centers

Answer 19

Global motion perception

Question 20

Example of global processing

Answer 20

Random dots
Gas molecules
Blood flow

Question 21

Example of local processing

Answer 21

Lights moving

Question 22

Degree of correlation as an indicator of motion sensitivity

Answer 22

Correlated motion

Question 23

When the striped patterns are seen through three circular apertures, they appear to all be moving in the same direction- up and to the left

Answer 23

Aperture problem

Question 24

Is aperture problem local or global

Answer 24

Local

Question 25

When the three rectangles are visible, their _____ provide clear motion cues that help your visual system interpret the true motion of the stripes within the circular apertures

Answer 25

Edges | Global

Question 26

Without the edges (global motion)

Answer 26

Your visual system finds the simplest explanation for the local motion of the stripes within the circular apertures, that they are all moving up and to the left

Question 27

What kind of cues help your visual system to resolve locally ambiguous motion

Answer 27

Global motion cues like an edge

Question 28

Motion aftereffect

Answer 28

- when viewing a stationary scene, the various neurons responses cancel each other out, so that not motion is perceived - when it starts moving, neurons sensitive to certain directional motion will increase their firing rate, leading to the perception of motion in that direction - after you watch the motion for long enough, the neurons will become fatuigued - when you stop the motion, the neurons will fire in a slowerrate compared to the neuron in opposite direction, causing the drifting (MAE)

Question 29

What does interocular transfer prove

Answer 29

That motions detectors are not in the retina as information from two eyes are combined

Question 30

Are motion detectors in the retina?

Answer 30

No, the interocular transfer proves this

Question 31

Motion induced blindness

Answer 31

Sometimes the brain ignores what the eyes tell it - left hemisphere suppresses sensory info that conflicts with its idea of what the world should be like - right hemisphere is the cautious deveils advocate, what you should actually be seeing

Question 32

Motion perception for more complex stimuli, such as texture-defined contours is called ______ motion stimuli

Answer 32

Second order

Question 33

Pathways for 1st and second order stimuli

Answer 33

Different pathways

Question 34

The fact that almost all humans can perceive second order motion is a strong indicator of what

Answer 34

The visual system does not simply track objects posterior over time to calculate movements, as this display demonstrates (since there are no objects to track)

Question 35

Highe velocity information processing

Answer 35

Magno pathway

Question 36

Low velocity information processing

Answer 36

Parvo pathways

Question 37

Visual area 5, MT, V5

Answer 37

Magno

Question 38

Motion processing

Answer 38

Magno

Question 39

Where system

Answer 39

Magno

Question 40

Dorsal pathway-parietal

Answer 40

Magno

Question 41

Motion perception-global stimuli

Answer 41

Magno

Question 42

Impertinent to magno

Answer 42

Akinetopsia

Question 43

Visual area V1-V2-V4

Answer 43

Parvo

Question 44

Object poreccsing

Answer 44

Parvo

Question 45

What system

Answer 45

Parvo

Question 46

Ventral pathway-temporal

Answer 46

Parvo

Question 47

Object perception (faces)

Answer 47

Parvo

Question 48

Impariment in parvo

Answer 48

Can't recognize objects

Question 49

Color detection

Answer 49

Parvo

Question 50

Black and white processing

Answer 50

Magno

Question 51

Direction, contrast, orientation, and speed

Answer 51

Magno

Question 52

There is evidence that the natural movements of humans and other animals, _______, may be processed differently than other forms of motion

Answer 52

Biological motion

Question 53

Function magentetic resonance imaging reveals the cortical _________ is activated when viwewing biological motion, but not artificial motion

Answer 53

Posterior superior temporal sulcus (STC)

Question 54

Another name for apparent motion

Answer 54

Illusional

Question 55

Under certain isoluminatnt conditions, the perception of motion is ______, it may be weak or slower than the actual movement of the bars

Answer 55

Impaired | -adding luminance contrast improves the perception of motion

Question 56

What part of the brain lit up when testing motion coherence

Answer 56

mediotemporal

Question 57

Magno pathway leaders to ______ perception, which leads to ____ motion

Answer 57

Motion | Rapid

Question 58

Where does all the info go to processing and distributed from

Answer 58

V1

Question 59

Central stream

Answer 59

V1,2,3

Question 60

Dorsal stream

Answer 60

MT

Question 61

Isoluminant

Answer 61

Same luminance

Question 62

Why is perception of motion impaired under isoluminant colors?

Answer 62

Since color and motion are different streams, the isoluminant colors will not help us determine the direction of motion

Question 63

Color is a poor stimuli for

Answer 63

Magno

Question 64

Color is good for

Answer 64

Parvo

Question 65

Higher temporal resolution

Answer 65

Magno

Question 66

More sensitive to low lights

Answer 66

Magno

Question 67

Monochromatic

Answer 67

Magno

Question 68

What cells are connected to magno

Answer 68

Rods

Question 69

Smaller RF, so better spatial resolution

Answer 69

Parvo

Question 70

Selective forcolor

Answer 70

Parvo

Question 71

What cells are connected to parvo

Answer 71

Cones

Question 72

High contrast with motion always looks for _____ to determine the motion

Answer 72

Edge

Question 73

High contrast vs low contrast edge

Answer 73

When it is low contrast, you can see the edge and it appears to move I'm steps, high contrast looks like they are moving step by step

Question 74

The edge information is only contained in ______ and the magno cannot see it

Answer 74

Color

Question 75

Objects appear to move ______ under rod mediated vision than under one mediated vision

Answer 75

Slower | -reason you need headlights on when driving at night

Question 76

Under mesopic conditions, where bothrods and cones are both active, motion perception is impaired because

Answer 76

An incomplete integration of rod and cone signals

Question 77

What effect does the velocity of a moving stimulus have on VA

Answer 77

As stimulus velocity increases, resolution acuity remains relatively constant up till 60-80 d/s Beyond this velocity, the dynamic VA deteriorates

Question 78

The reduction in dynamic visual acuity as target velocity increases is apparently due to the inability to accurately follow the stimulus with tracking (or following) eye movements, referred to as

Answer 78

Smooth eye pursuits

Question 79

There is evidence that higher dynamic visual acuity is associated with __________ while driving

Answer 79

Improved ability to detect hazardous situations

Question 80

Reason we dont see blurring during smooth pursuits

Answer 80

Saccadic suppression

Question 81

The ballistic eye movement between two fixation points is referred to as a

Answer 81

Saccadic eye movement

Question 82

Note that as you move your eyes from finger to finger or from any object to another object, the visual world remains still and cleat. This is in spite of the movement of images across your retina as you move your eyes

Answer 82

Vision is suppressed shortly before, during, and shortly after saccadic eye movments. This phenomenon, called saccadic suppression and saccadic omission, enables us to look from one object to another without smearing. Because magno pathway is sensitivt to high velocity movement, it is presumable suppressed to avoid smearing of vision

Question 83

It is found that neurons, providing eveidence that a primary contributor to saccadic suppression is

Answer 83

Extraretinal signal | Magno

Question 84

Saccadic suppression is a

Answer 84

Extraretinal signal | Magno

Question 85

What leads to the perception of motion

Answer 85

Changes in the spatial distribution of light, over time

Question 86

When we perceive real motion, light slides across the ____

Answer 86

Retina

Question 87

Apparent motion depends on two things to create a sense of motion

Answer 87

Separation of two stimuli | Appropriate time interval rate

Question 88

Which of the following is a first order stimuli for motion

Answer 88

Sine wavegrating

Question 89

Stimuli that consist of a linear exchange of dark and light are used to study

Answer 89

First order motion perception

Question 90

Coherence motion thresholds are defined useing

Answer 90

Random dot kinematograms

Question 91

As the coherence in a random dot kinetograms increases, the perception of motion

Answer 91

Increases

Question 92

Random dot kinematograms are used for

Answer 92

Global motion perception

Question 93

When stripped patterns seen through circular apertures appear to be all moving in the same direction, is know as

Answer 93

Aperture problem

Question 94

Interocular transfer study proved information from two eyes are

Answer 94

Combined

Question 95

The lack of perceived movement as fixation from one point to another is due to suppression of which pathway

Answer 95

Magno

Question 96

Which system in the higher order processing integrates information from both magno and parvo

Answer 96

V1

Question 97

A persons inability to recognize an object to the impairment of

Answer 97

Parvo

Question 98

The movement of slowl moving stimuli encoded by which pathway

Answer 98

Parvo

Question 99

Which retinogeniculate pathway processes most input to the dorsal processing

Answer 99

Magno

Question 100

Which are of the brain may be specific analyze biological motion

Answer 100

Posterior superior temporal sulcus

Question 101

Color is a good stimulus for

Answer 101

Parvo

Question 102

When compared to photopic conditions viewed under scoptopic conditions, a stimulus appears

Answer 102

25% slower

Question 103

The ability to resolve the moving stimuli is called as

Answer 103

Dynamic visual acuity (60-80)

Question 104

Vision suppressed shortly before during shortly aftersaccadic eye movement

Answer 104

Saccadic mission