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Flashcards in Tutorial week 9: colour Deck (46)
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1

What color do you see when a light passes through both the red filter and the green filter?

yellow

2

what is the problem with colour constancy

a particular wavelength combination reflected from a surface (and the particular combination of excitation in the 3 cone types) can yield experience of different colors in different situations.

3

___________ applies to all sensory systems. it is fundamental to understanding perception and you should make sure you understand it well.

the concept of receptive field

4

______________ is used to describe the part of the sensory surface that an environmental stimulus must impinge upon to make a neuron fire.

receptive field

5

__________ short wavelength

blue

6

_________ longer wavelength

red

7

_________ middle wavelength

green

8

___________ colour is caused by the lightness in the surrounding scene

black

9

_____ and ______ is when colour constancy is achieved

V1 and V4

10

__________ is where the primary visual cortex is located

VI

11

_______ color-coded cells

V4

12

______ cells responding to moving objects

V5

13

Neurons in the visual cortex work the same way, except they respond when there is a light stimulating the ___________.

retina

14

Neurons also have non-spatial ___________________. this describe the type of stimulus necessary to make the neuron work.

tuning characteristics

15

for ____________ it's the same, not all touch neurons respond to the same type of touch: if pressure on a patch of skin makes a neuron in this cortex fire, the same neuron might not respond to changes in temperature.

somatosentation

16

___________ refers to our ability to perceive different objects as always having the same colour independently of where we see them, or in what lighting conditions.

color constancy

17

lighting is __________

artificial

18

_____________ is different from artificial light

sunlight

19

the light reaching us from the atmosphere is ____________

blue

20

colour constancy sometimes discount the ___________ because somehow the variation is discounted.

illuminant

21

what lobe is responsible for vision - the visual cortex.

occipital lobe

22

the cortical processes that provide colour constancy are not well understand, what is known is that some cells found in the first part of the visual cortex - ___________ - are tuned for a certain combination of wavelength of light, more specifically they sum up the different cones excitation with a different weight for each cone. These cells get their input from the ___________.

area V1

photoreceptors

23

In _________cells respond in more complex fashion. in a way that corresponds more to the perceived colour of an object. in other words, cells in ________ have activity that parallels our conscious experience.

area V4

24

inside is to _________ as outside is to ________

artificial light
in bluer natural light

25

What area is tuned for yellow

V4

26

in ___________, the surface appears yellow will reflect lots of long (reddish) and middle (greenish) wavelengths, but not much short (blueish). here, we could find cells that would fire to this combination of reflected light. if the surface is outside, the reflected light will be different, it will contain more short wavelengths because of the blue light and proportionality less long and middle wavelength. in this area, the cells that fired inside will not fire now, different cells will respond, so constancy is NOT apparent. in this area, but it is in V4.

V1

27

What have experiments demonstrated that is critical to colour constancy

wavelength distribution

28

the perceived colour of an object depends on the relative amount it excited in the 3 kinds of cone and the ____________ in each of the 3 come channels

relative brightness

29

humans have 3 types of ________ and that objects in the world reflect light of different ____________

wavelength sensitive photo-receptors

Wavelength

30

_______________ is a property of the environment.

reflected light