Week 2: Perception in Action

Question 1

Who came up with ecological theory?

Answer 1

Gibson

Question 2

What did Gibson argue in ecological theory?

Answer 2

Perception can be explained exclusively by the environment and internal representations are not needed

Question 3

How is ecological theory bottom up?

Answer 3

Argues the mechanism is innate and needed for survival

Perception is direct so we don’t need to form a hypothesis first

Question 4

Is ecological theory bottom up or top down?

Answer 4

Bottom up

Question 5

How did Gibson use the example of piolets to support his theory?

Answer 5

As they land on the runway, their perception remained stationary on a fixed point and the landscape outside of that flowed outwards as they got closer

Question 6

What is optic flow?

Answer 6

The expansion and contraction of a scene which then provides detailed information about distance and speed

Question 7

What is the gradient of flow?

Answer 7

How much a scene expands or contracts gives us depth perception

Question 8

What is the focus of expansion?

Answer 8

The point in the distance where there is no flow.

In order to know where you’re going, you don’t need to judge the world, only use the mechanisms to detect the focus of expansion

Question 9

What is optic array?

Answer 9

The different intensities of light shining in different directions during movement

Question 10

How is optic array important for movement?

Answer 10

The light intensity changes in different directions and gives us information about our environment

Question 11

What is affordance?

Answer 11

The ability to discern possabilities of action within an environment - detecting all possible uses of an object

Question 12

What is resonance?

Answer 12

The way in which we pick up invariant information much like a radio tuning into a frequency

Question 13

What are the strengths of Gibson’s ecological theory?

Answer 13

Ecologically valid
Applicable to driving/piolets
Explains perception when cognitions are clear
Recognises how perception guides behaviour
Highlights the rich information in the optic array

Question 14

What are the flaws in Gibson’s ecological theory?

Answer 14

Reductionist
Doesn’t account for LTM or how the brain is involved
Nature - not balenced
Only true when our eyes are fixed in the direction of movement

Question 15

What is the view of neo-Gibsonians?

Answer 15

Perception and action systems are coupled to interpret environmental constraints and produce skilled movements

Optic flow - bottom up
We look at the most relevant areas of a scene - top down

Question 16

What did Land and Lee find in the driving study?

Answer 16

When travelling straight, the driver looks ahead but not on the focus of expansion
When going round a bend, they look at a tangent point on the side of the road

Question 17

What is time to contact?

Answer 17

A form of perception where we can judge when an object will hit us by looking at:

• the size and it’s change
• how far away it is

We can incorperate these to estimate how long the object will take to each us

Question 18

What single variable can be used to explain time to contact?

Answer 18

The rate of expansion - the faster the image is expanding, the less time to contact

Question 19

What is Tau?

Answer 19

The inverse rate of expansion of a retinal image - judges TTC

Question 20

What are some issues with Tau being used to calculate time to contact?

Answer 20

It ignores when objects accelerate
Only provides information relative to eyes, not if you’re driving and need to stop your car
Only accurate with symetrical objects

Question 21

What two types of depth cue do we use to perceive motion?

Answer 21

Monocular and binocular cues

Question 22

What are mononocular depth cues?

Answer 22

The segmentation of the fireground and background

Motion parallax

Question 23

What is motion parallax?

Answer 23

Objects closer to us will move further in our field of vision when we move compared to objects further away

Question 24

What are binocular depth cues?

Answer 24

Tau and compuring the distance to various objects

Things further away more across the retina slowly

Question 25

What wa Johansson’s study into biological movement perception?

Answer 25

Attatched lights to actors joints and asked participants to judge movement and posture

Argued that we have an innate (bottom up) ability to percieve motion and infer attention from it

Question 26

What is motion smoothness and what are it’s effects?

Answer 26

The smoothness of movement

People who more smoothly are seen as more attractive, trustworthy and competant

Question 27

What are mirror neurons?

Answer 27

Our ability to percive motion is based on immitation

Those who are skilled in movement (such as dancers) have more premotor activity when viewing videos of other dancers which suggests it influences observation

They help to immitate observed actions

Question 28

What is the moving room paradigm and how does it show vision and balence are linked

Answer 28

When the wall moves backwards, 12-18 month olds will fall and adults will sway

Optic flow is important in helping us to maintain balence

Question 29

Why is the vestibular system important in movement?

Answer 29

It assists with orientation and senses changes speed with the pull of gravity

Question 30

What is propriceptive information?

Answer 30

Used to identify the position of limbs and where we are in space

Question 31

What is developmental coordination disorder?

Answer 31

Movement disorder affecting the development of motor control and coordination. Skills are below expected for a person’s age and leads to issues with handwriting and riding a bike

Question 32

What percentage of 5-11 year olds have developmental coordination disorder?

Answer 32

5-6%