Which cells mediate interactions between photoreceptors and bipolar cells?

Which cells mediate interactions between photoreceptors and bipolar cells?

• A. Amacrine cells
• B. Ganglion cells
• C. Horizontal cells
• D. Müller glia

Answer: (C)

Horizontal cells act at the outer retina to connect photoreceptors with neighboring photoreceptors and bipolar cells, providing lateral interaction that shapes the signal before it reaches bipolar cells. They receive input from photoreceptors and send inhibitory feedback to surrounding photoreceptors, as well as influence the bipolar cells they contact. This lateral inhibition creates center-surround receptive fields, which enhances contrast and edge detection right at the first synapse in the visual pathway. In contrast, amacrine cells operate later in the inner retina between bipolar and ganglion cells, ganglion cells are the output neurons that send signals to the brain, and Müller glia provide support and metabolic maintenance. So, the mediator between photoreceptors and bipolar cells is the horizontal cell.

Horizontal cells act at the outer retina to connect photoreceptors with neighboring photoreceptors and bipolar cells, providing lateral interaction that shapes the signal before it reaches bipolar cells. They receive input from photoreceptors and send inhibitory feedback to surrounding photoreceptors, as well as influence the bipolar cells they contact. This lateral inhibition creates center-surround receptive fields, which enhances contrast and edge detection right at the first synapse in the visual pathway. In contrast, amacrine cells operate later in the inner retina between bipolar and ganglion cells, ganglion cells are the output neurons that send signals to the brain, and Müller glia provide support and metabolic maintenance. So, the mediator between photoreceptors and bipolar cells is the horizontal cell.