The revelation effect: when disguising test items induces recognition.

Documented here is a bias whereby items are more likely to be judged as having been presented beforehand if they are disguised in some way and so have to be discovered or "revealed." The bias was found for test words that were unfolded letter by letter (Experiments 1 and 3), presented with their letters either transposed (Experiments 2 and 3), or individually rotated (Experiments 4 and 5), or rotated as a whole (Experiment 5), and for test numbers that were presented in the form of roman numerals (Experiment 6) or equations (Experiment 7). The bias occurred both for items that were presented beforehand and for those that were not. No bias was found when words were judged, not for prior occurrence, but for typicality as category instances (Experiment 8), lexicality (Experiment 9), frequency of general usage (Experiment 10), or number of times encountered during the preceding week (Experiment 11).