Letter detection with rapid serial visual presentation: Evidence against word superiority at feature extraction.

Abstract
Letter detection typically is faster and more accurate in words than nonwords. Experiments 1, 2, and 3 tested the robustness of the word superiority effect using rapid serial visual presentation of words or nonwords. Letter detection was better in words even when the six-letter items were presented one after the other at rapid rates, up to about 10 items per second. At yet faster rates, however, the word advantage vanished. Experiments 4 and 5 tested whether word context aids feature extraction or the subsequent interpretation stage. In Experiment 4, subjects had to discriminate whether a mutilated A or mutilated E was present; in Experiment 5, subjects had merely to decide whether a mutilated A was present. Mutilation discrimination in Experiment 4 was better on words than nonwords; once a mutilation was detected, the word context revealed whether it was an A or an E. Mutilation detection in Experiment 5 did not differ between words and nonwords, though on words there was a response bias toward not reporting a mutilation as present. The results indicate that familiarity aids the interpretation process alone: Letters are not seen any more clearly or rapidly in words, but are simply filled in or inferred more accurately from the familiar context.