Developmental Anatomy Physiology Behaviour Computational
How We See
As we look around, our eyes and brain are continuously extracting useful information from our visual environment. Understanding how vision works is vital. From a clinical perspective we need to understand how normal vision works in order to diagnose when it is going wrong, help people with eye disease make the most of their vision, and assess the efficacy of new eye treatments. Understanding vision is also important from a basic scientific perspective. Because we find seeing so effortless, it may not be obvious that the brain is solving a series of tremendously difficult problems in order to guide our everyday behaviour. A deeper understanding of the human brain must involve a better understanding of vision.
Since vision is such a tremendously complex system – with around half of the human brain being involved in some way –we use a variety of scientific techniques to better understand it. Let us take the analogy of trying to understand how a car works. We can study the structure of engine parts: this is the approach taken in anatomy, which is concerned with the structure and connections between the cells making up the visual system. We could also run the engine and look at the operation of engine-parts– this is analogous to physiology where one assesses the operation of cells in a working visual system. If we could access the factory during construction of a car we could observe the development of the car as workers assembled and tested the parts. Another approach see how it performs under different driving conditions - this is like psychophysics, where one measures the limits of peoples' performance on simple visual tasks and from this infers how the visual system works. Finally, one could take everything one has learned from the other disciplines to build a simulated car: this is computational modelling.