Effects of element features on discrimination of relative numerosity: comparison of search symmetry and asymmetry pairs

  • Midori TokitaEmail author
  • Akira Ishiguchi
Original Article


We investigated effects of element features on statistical description of relative frequency. In Experiment 1, we manipulated the proportion of two elements types forming a set and the set size and measured response time and the accuracy of relative numerosity discrimination. We did this with element pairs that had been shown to produce search symmetries or asymmetries in visual search task. We found that pop-out elements in the search asymmetry pair were numerically overestimated. In Experiment 2, we used sets of circles and circles with gaps to eliminate the possibility that the overestimation found in Experiment 1 was due to larger contour length of pop-out elements. In Experiment 3, we manipulated proportion of two elements types and the set size to measure point of subjective equality (PSE) and the slopes of z-score functions in relative numerosity discrimination to support the results of Experiments 1 and 2. The results generally showed that the proportion of pop-out elements is likely to be overestimated and that set size had no effect, suggesting that the types of features characterized by visual search could influence the accuracy and precision in discrimination of relative numerosity.


Psychometric Function Search Asymmetry Relative Numerosity Numerosity Discrimination Proportion Judgment 
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  1. Allik, J., Tuulmets, T., & Vos, P. G. (1991). Size invariance in visual number discrimination. Psychological Research, 53, 290–295.CrossRefPubMedGoogle Scholar
  2. Averbach, E. (1963). The span of apprehension as a function of exposure duration. Journal of Verbal Learning and Verbal Behavior, 2, 60–64.CrossRefGoogle Scholar
  3. Barth, H., Kanwisher, N., & Spelke, E. (2003). The construction of large number representations in adults. Cognition, 86, 201–221.CrossRefPubMedGoogle Scholar
  4. Beck, D. M., & Kastner, S. (2005). Stimulus context modulates competition in human extrastriate cortex. Nature Neuroscience, 8, 1110–1116.CrossRefPubMedGoogle Scholar
  5. Burgess, A., & Barlow, B. H. (1983). The precision of numerosity discrimination in arrays of random dots. Vision Research, 23, 811–820.CrossRefPubMedGoogle Scholar
  6. Cantlon, J. F., & Brannon, E. M. (2006). Shared system for ordering small and large numbers in monkeys and humans. Psychological Science, 17, 401–406.CrossRefPubMedGoogle Scholar
  7. Chong, S. C., & Treisman, A. (2004). Attentional spread in the statistical processing of visual displays. Perception & Psychophysics, 66, 1282–1294.Google Scholar
  8. Dehaene, S. (1997). The Number Sense: How the mind creates mathematics. New York: Oxford University Press.Google Scholar
  9. Dehaene, S., Dupoux, E., & Mehler, J. (1990). Is numerical comparison digital? Analogical and symbolic effects in two-digit number comparison. Journal of Experimental Psychology: Human Perception and Performance, 16, 626–641.CrossRefPubMedGoogle Scholar
  10. Durgin, F. H. (1995). Texture density adaptation and the perceived numerosity and distribution of texture. Journal of Experimental Psychology: Human Perception and Performance, 149, 149–169.CrossRefGoogle Scholar
  11. Hollands, J. G., & Spence, L. (2001). The discrimination of graphical elements. Applied Cognitive Psychology, 15, 413–431.CrossRefGoogle Scholar
  12. Hurewitz, F., Gelman, R., & Schnitzer, B. (2006). Sometimes area counts more than number. Proceedings of the National Academy of Sciences of the United States of America, 103, 19599–19604.CrossRefPubMedGoogle Scholar
  13. Julesz, B. (1984). A brief outline of the texton theory of human vision. Trends in Neuroscinece, 7, 41–45.CrossRefGoogle Scholar
  14. Kadosh, R. C., Kadosh, K. C., & Henik, A. (2008). When brightness counts: The neuronal correlate of mumerical–luminance interference. Cerebral Cortex, 18, 337–343.CrossRefGoogle Scholar
  15. Moyer, R. S., & Landauer, T. K. (1967). Time required for judgments of numerical inequality. Nature, 215, 1519–1520.CrossRefPubMedGoogle Scholar
  16. Nothdurft, H. C. (1993). The role of features in preattentive vision: Comparison of orientation, motion and color cues. Vision Research, 33, 1937–1958.CrossRefPubMedGoogle Scholar
  17. Reynolds, J. H., & Desmone, R. (2003). Interacting roles of attention and visual salience in V4. Neuron, 37, 853–863.CrossRefPubMedGoogle Scholar
  18. Ross, J. (2003). Visual discrimination of number without counting. Perception, 32, 867–870.CrossRefPubMedGoogle Scholar
  19. Rubenstein, B. S., & Sagi, D. (1990). Spatial variability as a liming factor in texture-discrimination tasks: Implications for performance asymmetries. Journal of Optical Society of America, 7, 1632–1643.CrossRefGoogle Scholar
  20. Shuford, E. M. (1961). Percentage estimation of proportion as a function of element type, exposure time, and task. Journal of Experimental Psychology, 61, 430–436.CrossRefGoogle Scholar
  21. Treisman, A. (2006). How the deployment of attention determines what we see. Visual Cognition, 14, 411–443.CrossRefPubMedGoogle Scholar
  22. Treisman, A., & Gelade, G. (1980). A feature integration theory of attention. Cognitive Psychology, 12, 97–136.CrossRefPubMedGoogle Scholar
  23. Treisman, A., & Gormican, S. (1988). Feature analysis in early vision: Evidence for search asymmetries. Psychological Review, 95, 15–48.CrossRefPubMedGoogle Scholar
  24. Treisman, A., & Souther, J. (1985). Search asymmetry: A diagnostic for preattentive processing of separable features. Journal of Experimental Psychology: General, 114, 285–310.CrossRefGoogle Scholar
  25. Trick, L. M., & Pylyshyn, Z. W. (1993). What enumeration studies can show us about spatial attention: Evidence for limited capacity preattentive processing. Journal of Experimental Psychology: Human Perception and Performance, 19, 231–351.CrossRefGoogle Scholar
  26. Trick, L. M., & Pylyshyn, Z. W. (1994). Why are small and large numbers enumerated differently? A limited-capacity preattentive stage in vision. Psychological Review, 101, 80–102.CrossRefPubMedGoogle Scholar
  27. Varey, C. A., Mellers, B. A., & Birnbaum, M. H. (1990). Judgments of proportion. Journal of Experimental Psychology: Human Perception and Performance, 16, 613–625.CrossRefPubMedGoogle Scholar
  28. Wolfe, J. M. (1998). What do 1,000,000 trials tell us about visual search? Psychological Science, 9, 33–39.CrossRefGoogle Scholar
  29. Wolfe, J. M. (2001). Asymmetries in visual search: An introduction. Perception & Psychophysics, 63, 381–389.Google Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Ochanomizu UniversityTokyoJapan

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