Does the optic disc contain rods, cones, both, or neither?

Does the optic disc contain rods, cones, both, or neither?

• A. Rods
• B. Cones
• C. Both
• D. Neither

Answer: (D)

Photoreceptors are not present at the optic disc. The optic disc is the point where retinal nerve fibers converge to form the optic nerve, so light-detecting cells aren’t located there. Rods and cones reside in the sensory retina elsewhere (rods mainly for motion and low light, cones for color and detail, with a high cone concentration in the macula and especially the fovea). Because there are no photoreceptors at the optic disc, that region cannot detect light, creating a natural blind spot in vision.

Photoreceptors are not present at the optic disc. The optic disc is the point where retinal nerve fibers converge to form the optic nerve, so light-detecting cells aren’t located there. Rods and cones reside in the sensory retina elsewhere (rods mainly for motion and low light, cones for color and detail, with a high cone concentration in the macula and especially the fovea). Because there are no photoreceptors at the optic disc, that region cannot detect light, creating a natural blind spot in vision.