Techniques in this course will reduce the time for each fixation (the assimilation of a group of words simultaneously) to less than a quarter of a second, and the size of fixation can be increased from one or two short words to as many as five words or half a line. Your eyes will be doing less physical work; rather than having as many as 500 tightly focused fixations per page, you will be making about 100, each of which is less fatiguing, and reading speed will exceed 1,000. w.p.m. on light material.
The Eye and its Movements
In order to understand how we read and how reading may be improved, we must first look a little at how the eye works. Light entering the eye is focused by the lens onto the retina, which lines the inside of the eye. The retina itself consists of hundreds of millions of tiny cells responsive to light. Some cells - the cones - respond to specific colours; others - the rods - to the overall light intensity. These cells are connected to a web of nerves extending over the retina, which relay information to the visual cortex.
The centre of the retina, called the fovea, is a small area in which the cells are much more tightly packed, so that the perception of images falling on the fovea is much sharper and more detailed than elsewhere on the retina. When we focus our attention on something, the light from that item is focused onto the fovea - this is called a fixation.
Taken From: The Speed Reading Course

