When reading from left to right, useful information acquired during each fixational pause is widely assumed to extend 14 to 15 characters to the right of fixation but just 3 to 4 characters to the left, and certainly no further than the beginning of the fixated word. However, this leftward extent is strikingly small and seems inconsistent with other aspects of reading performance and with the general horizontal symmetry of visual input. Accordingly, 2 experiments were conducted to examine the influence of text located to the left of fixation during each fixational pause using an eye-tracking paradigm in which invisible boundaries were created in sentence displays. Each boundary corresponded to the leftmost edge of each word so that, as each sentence was read, the normal letter content of text to the left of each fixated word was corrupted by letter replacements that were either visually similar or visually dissimilar to the originals. The proximity of corrupted text to the left of fixation was maintained at 1, 2, 3, or 4 words from the left boundary of each fixated word. In both experiments, relative to completely normal text, reading performance was impaired when each type of letter replacement was up to 2 words to the left of fixated words but letter replacements further from fixation produced no impairment. These findings suggest that key aspects of reading are influenced by information acquired during each fixational pause from much further leftward than is usually assumed. Some of the implications of these findings for reading are discussed
