A memory-based interference effect in midstream order deficit

Abstract

People do not accurately recognize the relative order of a letter sequence displayed in a rapid serial visual presentation when the letter sequence is presented repeatedly and the exposure of the letters is very brief in the first half of the presentation. This phenomenon is known as midstream order deficit (MOD), and is considered to reflect the limitation of temporal resolution in segmentation processes. However, the results from three experiments revealed that MOD occurred even when the stimuli induced exogenous segmentation. Furthermore, a MOD-like effect could be observed when an irrelevant letter sequence was presented before the target letter sequence. We propose a new explanation for MOD, based on interference between the representations of order in memory and current perception. Copyright 2007 Psychonomic Society, Inc.