New research supported by the National Eye Institute may help explain how people with retinal degenerative disease can maintain their night vision for a relatively long period of time.
Researchers at the John A. Moran Eye Center at the University of Utah found that that second-order neurons in the retina, which relay visual signals to the retinal ganglion cells that project into the brain, play a key role. These neurons are able to maintain their activity in response to the degeneration of rod photoreceptors, or the cells responsible for allowing us to see at night. It’s a process known as homeostatic plasticity.
Studying a model of retinitis pigmentosa, the researchers determined that degeneration of rod photoreceptors triggered genomic and molecular changes in the retina and increased electrical signaling between rod photoreceptors and rod bipolar cells. These changes were associated with well-maintained behavioral night vision despite extensive photoreceptor cell loss. The findings were published in the journal eLife.