Visual sharpness contingency in recognition memory for orientation: mnemonic illusion suppressed by sensory signature.

A striking finding about human memory is that people's level of accuracy in remembering the orientation of heads on coins is often not simply at the chance level but significantly below it. However, S. W. Kelly, A. M. Burton, T. Kato, and S. Akamatsu (2001) reported that this is not so when two-alternative forced-choice visual recognition is employed. The Kelly et al. result could not be replicated here with a copy of their stimuli. However, the result was successfully replicated with newly created stimuli. A series of experiments provided converging evidence that the mnemonic illusion is suppressed when recognition alternatives possess sharp visual detail. The role of a sensory signature in suppressing the mnemonic illusion and in modulating visual recognition performance in general is delineated.