Visual Motion Moodle

Question 1

We can think of motion in four types:

Answer 1

1. Real motion
2. Apparent motion
3. Induced motion
4. The motion after-effect

Question 2

Real motion:

Answer 2

An object is moving through our visual field

Question 3

Apparent motion:

Answer 3

Static images presented in rapid succession

Question 4

Induced motion

Answer 4

Movement of part of the image causes perception of motion in another part

o eg the moon through clouds

Question 5

motion aftereffect

Answer 5

after prolonged of viewing a moving stimulus, a stationary scene will appear to move in the opposite direction

Question 6

motion aftereffect is sometimes called:

Answer 6

waterfall illusion

Question 7

biological motion

Answer 7

we are especially sensitive to the familiar motion of a moving person or animal
even when the motion is only represented by finite points of light
this is apparent when looking at a “point-light walker”

Question 8

watching a movie is an example of:

Answer 8

apparent motion

Question 9

movement of clouds that make the moon appear to move is an example of:

Answer 9

induced motion

Question 10

What is motion?

Answer 10

The change in position over time

Question 11

To detect motion, we need to

Answer 11

capture the output from the second receptive field, and the delayed output from the first receptive field

Question 12

What was proposed by Reichardt:

Answer 12

to detect motion in either direction, we need to mirror this circuit

Question 13

evidence of Reichardt motion detectors have been found in:

Answer 13

insects

Question 14

Reichardt motion detectors:

Answer 14

Can also explain the motion aftereffect

Question 15

motion detectors don’t

Answer 15

cover a very large area

Question 16

To detect motion over a bigger area,

Answer 16

Several of these simple detectors can be joined together

Question 17

Are motion detectors perfectly selective for a specific direction?

Answer 17

no

Question 18

motion detectors will respond most strongly to:

Answer 18

motion in their preferred direction

Question 19

motion detectors will respond less strongly to:

Answer 19

other directions they do not prefer depending on how close they are to the preferred direction

Question 20

Define the aperture problem:

Answer 20

When a moving object is viewed through an aperture (restricted window), the direction of motion may be ambiguous

Question 21

How might we overcome the limitation of the aperture problem?

Answer 21

Idea of a global motion detector

Question 22

A global motion detector:

Answer 22

Combining multiple local motion detectors!

Question 23

Reichardt motion detectors incorporate a __ to signal when an object has been moved between two adjacent receptive fields

Answer 23

delay element

Question 24

Reichardt motion detectors can account for the :

Answer 24

motion after-effect

Question 25

small receptive fields result in:

Answer 25

ambiguous motion perception because of the aperture problem

Question 26

___ can “solve” the aperture problem by combining the signals from multiple Reichardt motion detectors

Answer 26

global motion detectors

Question 27

sources of visual motion

Answer 27

visual motion can be:

1.motion of our environment
2.self-motion
3.eye-movements

Question 28

self-motion causes:

Answer 28

optic flow

Question 29

In self motion, the focus of expansion informs us of:

Answer 29

The direction we are moving

Question 30

How many types of eye movements:

Answer 30

5

Question 31

What are the five types of eye movement:

Answer 31

1. Fixation
2. Smooth pursuit
3. nystagmus
   4.Saccades
4. Vergence

Question 32

Describe fixation:

Answer 32

Eyes are completely still (for purpose of this course)

may include microsaccades, drift, tremor

Question 33

Is smooth pursuit under voluntary control?

Answer 33

NO!

Question 34

Describe nstagmus eye movement:

Answer 34

tracking eye movement: tracking only in one direction
slow tracking, jump back
visual stabilizing reflex

Question 35

Describe Saccades

Answer 35

change position of eye from one place to another
voluntary eye movement

Question 36

Describe vergence:

Answer 36

convergence: turning inwards
divergence: turning outwards

we do this so both our eyes can fixate same point

Question 37

How many muscles control eye movement

Answer 37

6 - 3 pairs

Question 38

Medial and lateral rectus responsible for

Answer 38

horizontal eye movement

Question 39

inferior and superior rectus responsible for:

Answer 39

vertical eye movement

Question 40

superior and interior oblique:

Answer 40

torsional movement

Question 41

if we fixate on the dot and move an object across our field of view, the image of that object

Answer 41

moves across our retina

Question 42

when we make an eye movement (or any movement), we use a copy of the motor command called ___ to predict the sensory consequences of that movement

Answer 42

corollary discharge

Question 43

when we make a saccadic eye movement, we ___ the visual information from during the saccade

Answer 43

don’t perceive

Question 44

evidence from monkeys suggest that we use the corollary discharge information to

Answer 44

remap the receptive field of frontal eye field (FEF) neurons to their future target just before an eye movement has started

Question 45

we ___ make smooth pursuit eye movements

Answer 45

cannot voluntarily