Fischer-Baum, S. 1 & McCloskey, M. 2
1 Beckman Institute, University of Illinois, Urbana-Champaign
2 Department of Cognitive Science, Johns Hopkins University
Perseverations errors, inappropriate intrusions of items from a previous trial into the current response, are observed in a variety of tasks. These errors provide a window into how the immediate past competes with current processing. Here, we analyze factors that predict which items are going to perseverate in three cognitive domains - spelling, spoken word production and verbal working memory. In each case, items from previous responses (e.g. the letter L in the written response MOTEL) intrude into subsequent responses (e.g. spelling “under” as UNDEL). A number of striking similarities were observed across the three domains. First, items occurring in a stimulus but not in the corresponding response do not perseverate into subsequent responses, whereas items occurring erroneously in a response do perseverate. Second, item perseverations are increasingly more likely with greater overlap between the current target and the previous response. Third, perseverated items tend to maintain position between the error and the previous response, specifically position defined relative to both the beginning and end of the sequence. We discuss how each of these results constrains theories of sequence representation and processing. Because similar results were found across cognitive domains, we suggest that perseverations reveal some general principles of sequential processing.