Question

According to the trichromatic (or Young-Helmholtz) theory of color vision, how do we tell the difference between bright yellow light and dim yellow light?

a. The dim light produces negative afterimages, but the bright light does not.
b. The bright light excites rods as well as cones, while the dim light excites only cones.
c. The bright light produces a greater total amount of activity by the cones than the dim light does.
d. The bright light produces a different ratio of firing by the three types of cones than the dim light does.

Answer 1

We tell the difference between bright yellow light and dim yellow light through the greater total amount of activity produced by the cones in response to bright light compared to dim light.

Step-by-step explanation:

According to the trichromatic theory of color vision, we tell the difference between bright yellow light and dim yellow light through the greater total amount of activity produced by the cones in response to bright light compared to dim light.

The trichromatic theory states that there are three types of cone cells in our eyes, each sensitive to different ranges of wavelengths of light. When bright yellow light enters our eyes, it activates the cones more strongly compared to dim yellow light, leading to a greater total amount of activity in the cones.