Final answer:
Retinal ganglion cells that have a red ON center and green OFF surround fire action potentials based on the opponent-process theory. This means they have an increased firing rate with red light in the center and decreased rate with green light in the surround. Baseline activity occurs with no color, and various responses are seen with different combinations of red and green light.
Step-by-step explanation:
To understand how ganglion cells would fire action potentials under different light conditions, it's important to comprehend how the retina processes visual information. In retinal ganglion cells that have a red ON center and green OFF surround, color perception is affected by the opponent-process theory, where certain cells are stimulated by red and inhibited by green, or vice versa.
- a. No color hitting the ganglion: The ganglion cells exhibit a baseline firing rate due to tonic activity.
- b. Red color hits the center only: The ganglion cell firing rate increases because the center is activated and the absence of green maintains normal inhibition in the surround.
- c. Red color hits the center and surround: The firing rate might increase less than in situation (b) because the surround will inhibit the center's response slightly due to lateral inhibition.
- d. Green color hits the surround only: The ganglion cell firing rate decreases since the OFF surround is activated, inhibiting the cell's activity.
- e. Green color hits the surround and red light wave hits the center only: This will likely cause an increase in firing rate, but less than in situation (b), because the red light activates the center and the green in the surround inhibits it.
The interplay of photoreceptor activity, lateral inhibition by horizontal cells, and influence from amacrine cells contributes to the ultimate response of the ganglion cells to color and light stimulation.