Which retinal cells are capable of generating action potentials and form the optic nerve?

Which retinal cells are capable of generating action potentials and form the optic nerve?

• A. Amacrine cells
• B. Photoreceptors
• C. Ganglion cells
• D. Horizontal cells

Answer: (C)

Signals leave the retina through retinal ganglion cells. These are the true output neurons of the retina: they integrate input from photoreceptors via bipolar and amacrine cells and then generate action potentials that travel along their axons. The axons of ganglion cells bundle together to form the optic nerve, carrying visual information to the brain. Photoreceptors and the interneurons (like horizontal and amacrine cells) mainly use graded changes in membrane potential to process and relay signals within the retina; they do not send long-range spikes to the brain or form the optic nerve.

Signals leave the retina through retinal ganglion cells. These are the true output neurons of the retina: they integrate input from photoreceptors via bipolar and amacrine cells and then generate action potentials that travel along their axons. The axons of ganglion cells bundle together to form the optic nerve, carrying visual information to the brain. Photoreceptors and the interneurons (like horizontal and amacrine cells) mainly use graded changes in membrane potential to process and relay signals within the retina; they do not send long-range spikes to the brain or form the optic nerve.