Although our body reacts to stimuli in the sensory system through the depolarization of neurons. In the retina, however, the photoreceptors (rods and cones) do not exhibit action potentials; rather, light activation causes a grade change in membrane potential and a corresponding change in the rate of transmitter release onto the postsynaptic neurons.
The reason why retina is mediated by graded potentials is because APs are not required to transmit information over the relatively short distances involved.
Hyperpolarization rather than depolarization occurs when light is shining on a photorecepter.
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