How Do We See?

The Eye and the Brain

In this course, Dr Daniel Baker (University of York) introduces the structure and function of the eye, and how alongside the brain it takes in and processes visual information. We begin by: (i) introducing how light enters the eye through its components such as the lens, cornea, the iris and retina; before (ii) discussing the pupil in more detail, and the properties of it that allow interesting phenomena such as red-eye to take place; and then (iii) learning about the light-sensitive rods and cones that enable us to see, as well as the differences between the two; which then follows onto (iv) the optic nerve and blind spot; and then finally (v) introducing how the brain processes visual information in the visual cortex.

How Do We See?

In the first mini-lecture, we introduce the sensory organ that allows us to see, the eye. The eye is introduced as part of the brain, as the connectivity between the two is quickly apparent as we appreciate the amount of the brain that is devoted to processing visual information. To begin, we discuss the journey that incoming light takes coming into the eye, allowing us to see visual stimuli. We discuss the importance of the lens, the cornea, the iris, and the retina. To finish off, we demonstrate using a binocular eye tracker to illustrate how the brain combines light intensity information from both eyes to determine how constricted both pupils should be.