Flashcards in Lecture 19 - Lecture 21: Vision Deck (79)
Light is a form of electromagnetic radiation generated by the oscillation of electrically charged particles called __________?
What are the two most important qualities we perceive from light?
Color and brightness
The length of the light's wavelength produces
As the length of the light wave increases, ___________________________
The sensation of the color changes
The brightness of a couloir is related to it's ____________, which is directly proportional to the density of photons in the wave.
The more photons in the wave, (brighter/lighter) the light or color will appear to be.
Light is a pattern of _________________ and _______________, along the many wavelength they create, that allow us to see the shapes and surfaces of objects.
Reflection and absorption
What is used to measure light?
Tendency for colors to remain fix despite changes in illumination In which they are embedded
Two types of reflection
1. Speculation reflection
2. Diffuse reflection
What is specular reflection
Mirror like reflection
What is diffuse reflection
Reflection of the rough
The first step in color perception begins with the _________ in the retina
What are the 3 different types of cones?
1. Absorbs light in short wavelengths (445 nm-blue)
2. Absorbs light at medium wavelengths (535nm-green)
3. Absorbs light at long wavelengths (570nm-red)
Red sensitive cones do not respond exclusively to long wavelengths of light, they just respond better - the same principle holds for the other 2 cones p. 71
We detect all these different wavelengths because the light energy reaching our eyes is __________ by the cones into neural impulses
______________ are special molecules imbedded in their membrane consisting of opsin and retinal
What are the 3 trichromatic colors?
Red, green, and blue
The trichromatic theory is also known as?
What is the problem with the trichromatic theory?
It could not explain the effect of negative after-images
What is the most common form of color blindness
Red (protanopia) - green (dueteranopia)
followed by the rarer blue-yellow form
(no such thing as red -blue or green-yellow color blindness)
Who proposed the opponent theory of color vision
Where does yellow come from?
It is made up from inputs arriving from the red and green cones
The perceived color of an object remains the same under very difficult lighting conditions
What colors do people who suffers are red-green color blind sees?
Blue, yellow, and grey
Why does red-green color blindness predominantly affect the males
Because the protan and duet an genes are located on the X-chromosomes, of which men have one and women have two. Women are rarely red-green blind because if one of their X chromosome is defective the other one can compensate for it. Daughters of men who handed down color blindness to his children will normally be unaffected
What type of color blindness would it be if a person lacks blue cones (unable to distinguish between blue and yellow).
_________________ causes total color blindness
First region to receive input from the lateral geniculate nucleus
Visual area 1 or v1 or area17 or primary visual cortex
18 and 19 or V2 and V3 make up the visual association cortex
Condition where people suffer from bilateral damage to the posterior regions of the parietal lobes