What is the role of horizontal and amacrine cells in retinal signal processing?

• A. They transmit signals directly to the brain without processing.
• B. Horizontal cells mediate lateral inhibition in the outer plexiform layer; amacrine cells modulate signals in the inner plexiform layer, contributing to temporal aspects and contrast.
• C. They generate action potentials as primary photoreceptors.
• D. They are involved in color detection only.

Answer: (B)