Tutorial week 9: colour Flashcards
(46 cards)
What color do you see when a light passes through both the red filter and the green filter?
yellow
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.
___________ 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
______________ is used to describe the part of the sensory surface that an environmental stimulus must impinge upon to make a neuron fire.
receptive field
__________ short wavelength
blue
_________ longer wavelength
red
_________ middle wavelength
green
___________ colour is caused by the lightness in the surrounding scene
black
_____ and ______ is when colour constancy is achieved
V1 and V4
__________ is where the primary visual cortex is located
VI
_______ color-coded cells
V4
______ cells responding to moving objects
V5
Neurons in the visual cortex work the same way, except they respond when there is a light stimulating the ___________.
retina
Neurons also have non-spatial ___________________. this describe the type of stimulus necessary to make the neuron work.
tuning characteristics
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
___________ 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
lighting is __________
artificial
_____________ is different from artificial light
sunlight
the light reaching us from the atmosphere is ____________
blue
colour constancy sometimes discount the ___________ because somehow the variation is discounted.
illuminant
what lobe is responsible for vision - the visual cortex.
occipital lobe
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
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
inside is to _________ as outside is to ________
artificial light
in bluer natural light