Abstract
Many mental tasks that involve operations on a number of items take place within a few hundred milliseconds. In such tasks, whether the items are processed simultaneously (in parallel) or sequentially (serially) has long been of interest to psychologists. Although certain types of parallel and serial models have been ruled out, it has proven extremely difficult to entirely separate reasonable serial and limitedcapacity parallel models on the basis of typical data. Recent advances in theory-driven methodology now permit strong tests of serial versus parallel processing in such tasks, in ways that bypass the capacity issue and that are distribution and parameter free. We employ new methodologies to assess serial versus parallel processing and find strong evidence for pure serial or pure parallel processing, with some striking apparent differences across individuals and interstimulus conditions.
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The second author received support from the same NIMH grant. Useful comments and insightful criticism was provided by the anonymous reviewers. We benefited from discussions with Saul Sternberg, Richard Schweickert, Michael Wenger, and Åse Innes-Ker. We also appreciate astute critiques from the editor and anonymous reviewers.
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Townsend, J.T., Fifić, M. Parallel versus serial processing and individual differences in high-speed search in human memory. Perception & Psychophysics 66, 953–962 (2004). https://doi.org/10.3758/BF03194987
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DOI: https://doi.org/10.3758/BF03194987