Journal of Cognitive Enhancement

, Volume 1, Issue 4, pp 434–454 | Cite as

N-back Versus Complex Span Working Memory Training

  • Kara J. BlackerEmail author
  • Serban Negoita
  • Joshua B. Ewen
  • Susan M. Courtney
Original Article


Working memory (WM) is the ability to maintain and manipulate task-relevant information in the absence of sensory input. While its improvement through training is of great interest, the degree to which WM training transfers to untrained WM tasks (near transfer) and other untrained cognitive skills (far transfer) remains debated and the mechanism(s) underlying transfer are unclear. Here we hypothesized that a critical feature of dual n-back training is its reliance on maintaining relational information in WM. In experiment 1, using an individual differences approach, we found evidence that performance on an n-back task was predicted by performance on a measure of relational WM (i.e., WM for vertical spatial relationships independent of absolute spatial locations), whereas the same was not true for a complex span WM task. In experiment 2, we tested the idea that reliance on relational WM is critical to produce transfer from n-back but not complex span task training. Participants completed adaptive training on either a dual n-back task, a symmetry span task, or on a non-WM active control task. We found evidence of near transfer for the dual n-back group; however, far transfer to a measure of fluid intelligence did not emerge. Recording EEG during a separate WM transfer task, we examined group-specific, training-related changes in alpha power, which are proposed to be sensitive to WM demands and top-down modulation of WM. Results indicated that the dual n-back group showed significantly greater frontal alpha power after training compared to before training, more so than both other groups. However, we found no evidence of improvement on measures of relational WM for the dual n-back group, suggesting that near transfer may not be dependent on relational WM. These results suggest that dual n-back and complex span task training may differ in their effectiveness to elicit near transfer as well as in the underlying neural changes they facilitate.


Cognitive training Working memory Transfer Alpha power 



We wish to thank Cody Elias, Antonio Vergara, Samantha Dunnum, Myranda Gormley, Leon Li, and Carolyn Xue for help with data collection.


This project was supported by a Johns Hopkins University Science of Learning Institute Fellowship to KJB, NIH grant R01 MH082957 to SMC, and grant K23 NS073626 to JBE.

Supplementary material

41465_2017_44_MOESM1_ESM.docx (771 kb)
ESM 1 (DOCX 770 kb)


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Kara J. Blacker
    • 1
    Email author
  • Serban Negoita
    • 1
  • Joshua B. Ewen
    • 1
    • 2
    • 3
  • Susan M. Courtney
    • 1
    • 4
    • 5
  1. 1.Department of Psychological & Brain SciencesJohns Hopkins UniversityBaltimoreUSA
  2. 2.Neurology and Developmental MedicineKennedy Krieger InstituteBaltimoreUSA
  3. 3.Department of NeurologyJohns Hopkins University School of MedicineBaltimoreUSA
  4. 4.Department of NeuroscienceJohns Hopkins University School of MedicineBaltimoreUSA
  5. 5.F.M. Kirby Center for Functional NeuroimagingKennedy Krieger InstituteBaltimoreUSA

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