Inside the eye, the light also forms a pattern on a light-sensitive layer. This layer, at the back of the eye, is called the retina(RET-in-uh).The cells of t. the retina respond to light. In contrast to a camera with film, the eye processes its images instantly. The cells of the retina send electrical impulses speeding along the optic nerve. When the impulses reach the brain, it makes sense of the image.