How to rewire the eye
Transforming nerve cells into light-sensing cells aims to restore sight in some blind patients
SEEING THE LIGHT The brain’s window on the visual world is a multilayered tissue at the back of the eye called the retina. Light-detecting rods and cones sit at the very back of the tissue. They pass information to the brain via bipolar cells and ganglion cells. Humans and some animals have sharp vision thanks to the fovea, a window in the retina that offers direct access to the cones.
Eye: Tony Graham/Getty Images, adapted by J. Hirshfeld; webvision.med.utah.edu, adapted by J. Hirshfeld
A man who had been blind for 50 years allowed scientists to insert a tiny electrical probe into his eye.