The effects of visual similarity on proofreading for misspellings

In three experiments, subjects read prose passages and circled misspellings in them. The misspelled words were created by replacing a single letter with another one. The visual similarity between the correct letter and the one that was substituted for it increased the percentage of proofreading errors. The results suggest that proofreaders search through a visual representation of the text and that a hierarchical feature test is applied to this representation, according to which subjects give first priority to resolving letter envelope and second priority to discriminating additional visual features. A sophisticated-guessing decision rule is also implicated for the misspellings that do not alter letter envelope: Subjects are tolerant of missing letter features but are intolerant of additional features.