To see under starlight and moonlight, the retina of the eye changes both the software and hardware of its light-sensing cells to create a kind of night vision. Retinal circuits that were thought to be unchanging and programmed for specific tasks are adaptable to different light conditions, say the Duke scientists who identified how the retina reprograms itself for low light.
“To see under starlight, biology has had to reach the limit of seeing an elementary particle from the universe, a single photon,” said Greg Field, an assistant professor of neurobiology and biomedical engineering at Duke University. “It’s remarkable at night how few photons there are.”
The findings, which appear early online in Neuron, show that the reprogramming happens in retinal cells that are sensitive to motion.