The mental representation of numerical fractions: real or integer?

Mario Bonato, Sara Fabbri, Carlo Umiltà, Marco Zorzi

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126 Citations (Scopus)


Numerical fractions are commonly used to express ratios and proportions (i.e., real numbers), but little is known about how they are mentally represented and processed by skilled adults. Four experiments employed comparison tasks to investigate the distance effect and the effect of the spatial numerical association of response codes (SNARC) for fractions. Results showed that fractions were processed componentially and that the real numerical value of the fraction was not accessed, indicating that processing the fraction's magnitude is not automatic. In contrast, responses were influenced by the numerical magnitude of the components and reflected the simple comparison between numerators, denominators, and reference, depending on the strategy adopted. Strategies were used even by highly skilled participants and were flexibly adapted to the specific experimental context. In line with results on the whole number bias in children, these findings suggest that the understanding of fractions is rooted in the ability to represent discrete numerosities (i.e., integers) rather than real numbers and that the well-known difficulties of children in mastering fractions are circumvented by skilled adults through a flexible use of strategies based on the integer components.

Original languageEnglish
Pages (from-to)1410-1419
Number of pages10
JournalJournal of Experimental Psychology : Human Perception and Performance
Issue number6
Publication statusPublished - Dec-2007
Externally publishedYes


  • Adult
  • Analysis of Variance
  • Aptitude
  • Attention
  • Awareness
  • Comprehension
  • Female
  • Humans
  • Male
  • Mathematics
  • Practice (Psychology)
  • Problem Solving
  • Reaction Time
  • Journal Article
  • Research Support, Non-U.S. Gov't

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