In the presence of light, what change occurs to the membrane potential of OFF-center bipolar cells?

In the presence of light, OFF-center bipolar cells undergo hyperpolarization. This response is a key feature of the retinal signaling pathway involving photoreceptor cells. When light hits the photoreceptors (rods and cones), it causes them to hyperpolarize, leading to a decrease in the release of neurotransmitters.

In OFF-center bipolar cells, which primarily respond to a decrease in illumination, this reduced release of neurotransmitters from photoreceptors results in a hyperpolarization of the bipolar cells. Essentially, when light is present, the OFF-center bipolar cells are less activated, therefore their membrane potential becomes more negative. This mechanism contrasts with ON-center bipolar cells, which depolarize in response to light, highlighting the distinct roles that different types of bipolar cells play in processing visual information.

Understanding the responses of these bipolar cells is crucial for grasping how visual signals are integrated in the retina before being transmitted to the brain.