Neural Activity in the Retina (IMAGE) NIH/National Eye Institute Caption Artist's rendering of neural activity in the retina. Light that enters the eye activates rod and cone photoreceptors, which then activates retinal ganglion cells. A signal travels to the brain via the retinal ganglion cell axons. Credit National Eye Institute Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.