Question

Compare and contrast the different theories of color vision and how the theories explain our perceptions. Include what roles the rods and cones play in these. How would our perception of the world change if we had only one cone? Two cones? Four cones?

Answer 1

Majorly there are two important theories of Color vision

1. Trichromatic theory (Young Helmholtz theory)

2. Opponent process theory

A) Trichromatic theory : According to this theory, there are three receptors in retina which are responsible for the color perception. First receptor is sensitive for Green, second one is sensitive to Blue and the third one is sensitive to Red. By combining these three Colors, any visible color in the spectrum can be formed.

B) Opponent process theory : According to this, three receptor complexes with opposing action conttco our ability to perceive color. These are the red-green complex, the blue-yellow complex and the black-white complex. According to this theory, cells can detect one color at a time because two colors opposes one another.

Rods and cones are photoreceptors in human retina. Rods are responsible for vision at the low light levels and have low spatial acuity. Where as cones are active at higher levels and they are responsible for higher spatial acuity.