@import "../images/journal_style.css"; @import "../images/article_style.css"; Online Issues ILAR Journal V40(2) 1999
Animal Models of Human Vision
Introduction
Richard C. Van Sluyters
The eye sends, as we saw, into the cell-and-fibre forest of the brain, throughout the waking day continual rhythmic streams of tiny, individually evanescent, electrical potentials. This throbbing streaming crowd of electrically shifting points in the spongework of the brain bears no obvious semblance in space-pattern, and even in temporal relation resembles but a little remotely the tiny two-dimensional upside-down picture of the outside world which the eyeball paints on the beginnings of its nerve-fibres to the brain. But that little picture sets up an electrical storm .... A shower of little electrical leaks conjures up for me, when I look at him approaching, my friend's face, and how distant he is from me they tell me. Taking their word for it, I go forward and my other senses confirm that he is there. (Sherrington 1940, p 128-129)
This lovely passage, written when the English physiologist Sir Charles Scott Sherrington was in his mid-eighties, elegantly captures the intricate beauty and compelling power of our visual sense. Most of what we learn and remember about the world is based on sight. The visual system is by far the most complex of our sensory systems. The two million axons in the optic nerves far exceed the total number of fibers in our other sensory nerves, including all the dorsal root fibers that enter the spinal cord. It is precisely because the sense of sight is so important in our daily lives that we value it so highly. A survey by the National Institutes of Health, National Eye Institute (NEI | |
|
