Psychonomic Bulletin & Review

, Volume 22, Issue 2, pp 366–377 | Cite as

Improving fluid intelligence with training on working memory: a meta-analysis

  • Jacky AuEmail author
  • Ellen Sheehan
  • Nancy Tsai
  • Greg J. Duncan
  • Martin Buschkuehl
  • Susanne M. Jaeggi
Theoretical Review


Working memory (WM), the ability to store and manipulate information for short periods of time, is an important predictor of scholastic aptitude and a critical bottleneck underlying higher-order cognitive processes, including controlled attention and reasoning. Recent interventions targeting WM have suggested plasticity of the WM system by demonstrating improvements in both trained and untrained WM tasks. However, evidence on transfer of improved WM into more general cognitive domains such as fluid intelligence (Gf) has been more equivocal. Therefore, we conducted a meta-analysis focusing on one specific training program, n-back. We searched PubMed and Google Scholar for all n-back training studies with Gf outcome measures, a control group, and healthy participants between 18 and 50 years of age. In total, we included 20 studies in our analyses that met our criteria and found a small but significant positive effect of n-back training on improving Gf. Several factors that moderate this transfer are identified and discussed. We conclude that short-term cognitive training on the order of weeks can result in beneficial effects in important cognitive functions as measured by laboratory tests.


Cognitive training Transfer Plasticity 


Author’s Notes

S. M. Jaeggi and M. Buschkuehl came up with the study concept and coded data. E. Sheehan and J. Au also coded data. J. Au performed the data analyses and drafted the manuscript. G. J. Duncan consulted regarding meta-analytical techniques. All authors contributed to the data interpretation and writing, and all authors read and approved the final manuscript.

Supplementary material

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Copyright information

© Psychonomic Society, Inc. 2014

Authors and Affiliations

  • Jacky Au
    • 1
    Email author
  • Ellen Sheehan
    • 1
  • Nancy Tsai
    • 1
  • Greg J. Duncan
    • 1
  • Martin Buschkuehl
    • 2
  • Susanne M. Jaeggi
    • 1
  1. 1.School of EducationUniversity of California, IrvineIrvineUSA
  2. 2.MIND Research InstituteIrvineUSA

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