Abstract
Participants judged the number of dots in visual displays with brief presentations (200 msec), such that the numerosity judgment was based on an instantaneous impression without counting. In some displays, pairs of adjacent dots were connected by line segments, whereas, in others, line segments were freely hanging without touching the dots. In Experiments 1, 2A, and 2B, connecting pairs of dots by line segments led to underestimation of dot numbers in those patterns. In Experiment 3, we controlled for the number of freely hanging line segments, whereas Experiment 4 showed that line segments that were merely attached to dots without actually connecting them did not produce a considerable underestimation effect. Experiment 5 showed that a connectedness effect existed when stimulus duration was reduced (50 msec) or extended (1,000 msec). We conclude that connectivity affects dot numerosity judgments, consistent with earlier findings of a configural effect in numerosity processing. Implications of the role of connectedness in object representation are discussed.
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This project was supported by Ministry of Science and Technology of China Grants 2005CB522800 and 2004CB318101, National Nature Science Foundation of China Grant 30621004, and Knowledge Innovation Projects Grant CSTD S2002-1 from the Chinese Academy of Sciences, with L.C. as the principal investigator and J.Z. as an overseas guest investigator
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He, L., Zhang, J., Zhou, T. et al. Connectedness affects dot numerosity judgment: Implications for configural processing. Psychonomic Bulletin & Review 16, 509–517 (2009). https://doi.org/10.3758/PBR.16.3.509
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DOI: https://doi.org/10.3758/PBR.16.3.509