Eye span

Our eye muscles are limited. If we were to focus on each word that we read, we would not be able to read above 600wpm and then we would suffer a huge headache and eyestrain. Students who try to push reading speed without learning saccades often complain that the words become blurry and they cannot read at all for 2 weeks before they can resume the regular speedreading. Clearly this does not happen to me, to Anna and to students that graduate the course. This is not because we have exceptional stamina, but because we read smarter.

Our eyes have a tiny spot in which they are focused. Outside of this spot our vision degrades and gets increasingly blurry. On edges of the peripheral vision, we can only notice large movements without being able to understand them. Therefore, our instinct is to focus on the word we read, the word after it and so on. However, we do not need our top resolution to understand the text we read.  We can read quite well even if our eyes are focused elsewhere. We do need some short adaptation before our brain rewires.

By focusing on one spot and picking up letters and words on different spots we increase our eye span, or the ability of the brain to interpret signals from visual areas with lower resolution.  This skill is notoriously hard for eyes and for the brain and for every couple of minutes of practice we need to take a couple of minutes of rest (focus our eyes on the horizon and relax).

Very soon, we will be able to see 5 words while focusing on the central word of the phrase. Advanced students see 12 words with one focus. These 5-12 words form a saccade.

Suppose our saccade is 7 words wide and an average text line in our book is 12 words. Then we can focus on 4th and 8th word of the line only and see 2 saccades with 3 words overlap. It is important to avoid overscan at the edges of the book, therefore we do not focus on the first word, but we need overlaps, since some words are very long and catch space of 2-3 regular words.

Suppose we have eye-span of 9 words, and we need overlap of 2 words. Then we can saccade with relative ease 7*500=3500 wpm. At 12 words saccade and 2 words overlap, we get ~5000wpm. This is probably the upper limit of our current method and the speed you should be using for your scanning technique. For scanning and skimming,

You can increase your speed even more by reading several lines at once. In fact, some people (me included) are capable of getting a full Kindle or iPad mini page in one span focusing in the middle of the screen. This is both very fast and very comfortable since I do not have to move my eyes often. However, this does not apply for very long lines, and the reading speed drops significantly as lines get wider.

By reading with the peripheral vision, we can increase reading speed and decrease eyestrain significantly. If your eyes hurt when reading, then you are not doing this correctly!