Psychonomic Bulletin & Review

, Volume 17, Issue 5, pp 673–679 | Cite as

Quantity, not quality: the relationship between fluid intelligence and working memory capacity

  • Keisuke Fukuda
  • Edward Vogel
  • Ulrich Mayr
  • Edward AwhEmail author
Brief Reports


A key motivation for understanding capacity in working memory (WM) is its relationship with fluid intelligence. Recent evidence has suggested a two-factor model that distinguishes between the number of representations that can be maintained in WM and the resolution of those representations. To determine how these factors relate to fluid intelligence, we conducted an exploratory factor analysis on multiple number-limited and resolution-limited measures of WM ability. The results strongly supported the two-factor model, with fully orthogonal factors accounting for performance in the number-limited and resolution-limited conditions. Furthermore, the reliable relationship between WM capacity and fluid intelligence was exclusively supported by the number factor (r=.66), whereas the resolution factor made no reliable contribution (r=−.05). Thus, the relationship between WM capacity and standard measures of fluid intelligence is mediated by the number of representations that can be simultaneously maintained in WM, rather than by the precision of those representations.


Work Memory Work Memory Capacity Fluid Intelligence Complex Span Change Trial 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Psychonomic Society, Inc. 2010

Authors and Affiliations

  • Keisuke Fukuda
    • 1
  • Edward Vogel
    • 1
  • Ulrich Mayr
    • 1
  • Edward Awh
    • 1
    Email author
  1. 1.Department of PsychologyUniversity of OregonEugene

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