Vision span

Application to speed reading

While reading, readers will fail to recognize a word unless they are fixating within three to four character spaces of the word. The same is true for speed readers and skimmers. Speed readers cannot answer questions about a main point or detail, if they did not fixate directly on it or within three character spaces of it. When a text is removed whilst reading, readers can only accurately report upon the word they were fixating upon or the next one to the right. There is no evidence from eye movement research that individuals are making predictions of text based upon hypotheses about the words in the periphery so that they can skip over or spend less time on unimportant or redundant words.

Most speed reading courses claim that the peripheral vision can be used to read text. This has been suggested impossible because the text is blurred out through lack of visual resolution. At best the human brain can only guess at the content of text outside the macular region. There simply are not enough cone cells away from the center of the visual field to identify words in the periphery of the field.

It has been suggested that the fixation span can be stretched through training (meta guiding) to take in as much as a line for the purpose of skimming or speed reading. However other sources suggest that using this method can result in a severely reduced comprehension rate in comparison to normal reading ("rauding").

Some speed reading courses stress that the human eye has to move very quickly. They also stress that the human eye should move in a pattern to fill in the information that was not properly perceived. The effective limit for scanning speeds based upon the limit of the human eye's resolution is about 300 words per minute. It is claimed that such speeds also require great practice, and extremely rapid eye movements, although research suggests that such training is not possible. It has been suggested by some speed reading promoters that the readers who achieve such speeds are on the autism spectrum. Research into reading rate suggests that study strategies, rather than speed reading, explains why expert readers, such as professors and editors, are more efficient than others.