How Do We See Colors?

Question 1

Young-Helmholtz Theory (trichromatic theory)

Answer 1

All colors would be mixtures of blue, green, and red based on response of those cone types

Question 2

Opponent-Process Theory

Answer 2

1. Three cone types: violet, green, and yellow; short, medium, and long wavelength cones
2. Each responds to many wavelengths, but peak responses are at: Short=440nm, Medium=530nm, Long=560nm
3. Colors come in opponent pairs: black and white, red and green, blue and yellow
4. Activation of short, medium, and long wavelength cones may excite or inhibit opponent process cells (which may be ganglion cells or cells in the thalamus or cortex)