CHAPTER 9 - Perceiving Colour

Question 1

Describe the case of Mr. I. What does it illustrate about colour perception?

Question 2

What are the various functions of colour vision?

Question 3

What physical characteristic of light is most closely associated with colour perception? How is this demonstrated by differences in reflection and transmission of light of different objects?

Question 4

Describe subtractive and additive colour mixing. How can the results of these two types of colours mixing be related to the wavelengths that are reflected into an observer’s eyes?

Question 5

What are spectral colours? Nonspectral colours? How many different colours can humans discriminate?

Question 6

What are hue, saturation, and value? Describe how the Munsell colour system represents different properties of colour

Question 7

What did Thomas Young say was wrong with Newton’s idea that colour is created by vibrations?

Question 8

How did Young explain colour vision? Why is his explanation called the Young-Helmholtz theory?

Question 9

Describe Maxwell’s colour matching experiments. How did the results support the trichromacy of vision?

Question 10

What is the connection between trichromacy and the cone receptors and pigments?

Question 11

What is metamerism? How is it related to the results of colour matching experiments?

Question 12

What is monochromacy? How does a monochromat match lights in a colour matching experiment? Does a monochromat perceive chromatic colour?

Question 13

What is the principle of univariance? How does the principle of univariance explain the fact that a monochromat can match any wavelength in the spectrum by adjusting the intensity of any other wavelength?

Question 14

Describe how pigment absorption spectra can explain how wavelength can be determined if there are only two receptor types

Question 15

How would colour matching results differ for a person with two types of cone receptors, compared to three?

Question 16

What is dichromacy? What procedure was used to determine how a dichromat’s colour vision compared to a trichromat’s?

Question 17

What are the three types of dichromacy?

Question 18

What did Hering’s opponent-process theory propose?

Question 19

What was Hering’s phenomenological evidence for opponent-process theory?

Question 20

Why wasn’t Hering’s theory widely accepted?

Question 21

Describe Hurvich and Jameson’s hue cancellation experiments. How was the result used to support opponent-process theory?

Question 22

What is the physiological evidence for opponency?

Question 23

What are unique hues?

Question 24

Describe the modern hue scaling experiments that used colours other than red, green, blue, and yellow as the “primaries.” What are the implications of these results?

Question 25

Has it been possible to establish a connection between the firing of opponent neurons and our perception of specific colours?

Question 26

What functions have been suggested for opponent neurons, in addition to their role in colour perceptino?

Question 27

Where is colour represented in the cortex? How are the colour areas related to areas for face and place processing?