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Journal of Cognitive Enhancement

, Volume 3, Issue 4, pp 416–424 | Cite as

No Enhancing Effect of Fronto-Medial tDCS on Working Memory Processes

  • Elisabeth V. C. Friedrich
  • Barbara Berger
  • Tamas Minarik
  • Doris Schmid
  • Charline Peylo
  • Paul SausengEmail author
Original Article
  • 90 Downloads

Abstract

It has been argued that transcranial direct current stimulation (tDCS) over the frontal cortex impacts, directly and indirectly, on oscillatory brain activity in the theta frequency range, and thus affects working memory. This study aims to clarify whether a tDCS montage with one electrode over a fronto-medial stimulation site and the return electrode on the chin can indeed modulate working memory performance. It was predicted that tDCS with the anode over the fronto-medial site should lead to better working memory performance compared to when the cathode is placed over the fronto-medial site. Eighty-four participants were divided into three groups receiving either 10-min sham, anodal, or cathodal stimulation at 2 mA offline between two blocks of a two-back task. No significant differences between stimulation conditions were found. Bayes statistics indicated moderate evidence that the null hypothesis is in fact true. This paper demonstrates that the fronto-medial tDCS montage has no functional impact on working memory performance. Future studies could investigate fronto-medial frequency-specific oscillatory electric stimulation in the theta frequency range. Such oscillatory electrical stimulation might be more successful than tDCS in modulating working memory processes.

Keywords

Transcranial direct current stimulation (tDCS) Frontal-midline theta Medial prefrontal cortex Negative findings 

Notes

Acknowledgements

We would like to thank Stella Berboth, Axel Smith, and the LMU psychology undergraduate students for help with the data collection.

Funding information

This research was funded by the German research council DFG SA1782/2-1.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

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References

  1. Antal, A., Keeser, D., Priori, A., Padberg, F., & Nitsche, M. A. (2015). Conceptual and procedural shortcomings of the systematic review “evidence that transcranial direct current stimulation (tDCS) generates little to- no reliable neurophysiologic effect beyond MEP amplitude modulation in healthy human subjects”: a systematic R. Lett to Ed. Brain Stimulation, 8, 838–849.Google Scholar
  2. Antal, A., Alekseichuk, I., Bikson, M., Brockmöller, J., Brunoni, A. R., Chen, R., et al. (2017). Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines. Clinical Neurophysiology, 128(9), 1774–1809.PubMedPubMedCentralGoogle Scholar
  3. Baddeley, A. D., Allen, R. J., & Hitch, G. J. (2011). Binding in visual working memory: the role of the episodic buffer. Neuropsychologia., 49(6), 1393–1400.PubMedGoogle Scholar
  4. Biel, A. L., & Friedrich, E. V. C. (2018). Why you should report Bayes factors in your transcranial brain stimulation studies. Frontiers in Psychology, 9(July), 1–4.Google Scholar
  5. Brickenkamp, R., Schmidt-Atzert, L., & Liepmann, D. (2010). Test d2 – Revision. Aufmerksamkeits- und Konzentrationstest. Göttingen: Hogrefe.Google Scholar
  6. Cowan, N. (2008). What are the differences between long-term, short-term, and working memory? Progress in Brain Research, 6123(07), 323–338.Google Scholar
  7. Dienes, Z. (2014). Using Bayes to get the most out of non-significant results. Frontiers in Psychiatry, 5(July), 1–17.Google Scholar
  8. Faul, F., Erdfelder, E., Lang, A.-G., & Buchner, A. (2007). G * power 3 : a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39(May), 175–191.Google Scholar
  9. Gevins, A., Smith, M. E., McEvoy, L., & Yu, D. (1997). High-resolution EEG mapping of cortical activation related to working memory: effects of task difficulty, type of processing, and practice. Cerebral Cortex, 7(4), 374–385.PubMedGoogle Scholar
  10. Glennon, M., Keane, M. A., Elliott, M. A., & Sauseng, P. (2016). Distributed cortical phase synchronization in the EEG reveals parallel attention and working memory processes involved in the attentional blink. Cerebral Cortex, 26(5), 2035–2045.PubMedGoogle Scholar
  11. Griesmayr, B., Berger, B., Stelzig-Schoeler, R., Aichhorn, W., Bergmann, J., & Sauseng, P. (2014). EEG theta phase coupling during executive control of visual working memory investigated in individuals with schizophrenia and in healthy controls. Cognitive, Affective, & Behavioral Neuroscience, 14(4), 1340–1355.Google Scholar
  12. Helfrich, R. F., Schneider, T. R., Rach, S., Trautmann-Lengsfeld, S. A., Engel, A. K., & Herrmann, C. S. (2014). Entrainment of brain oscillations by transcranial alternating current stimulation. Current Biology, 24(3), 333–339.PubMedGoogle Scholar
  13. Herrmann, C. S., Rach, S., Neuling, T., & Strüber, D. (2013). Transcranial alternating current stimulation: a review of the underlying mechanisms and modulation of cognitive processes. Frontiers in Human Neuroscience, 7(June), 1–13.Google Scholar
  14. Hill, A. T., Fitzgerald, P. B., & Hoy, K. E. (2016). Effects of anodal transcranial direct current stimulation on working memory: a systematic review and meta-analysis of findings from healthy and neuropsychiatric populations. Brain Stimulation, 9(2), 197–208.PubMedGoogle Scholar
  15. Horvath, J. C. (2015). New quantitative analyses following price & Hamilton’s critique do not change original findings of Horvath et al. Brain Stimulation, 8(3), 665–666.PubMedGoogle Scholar
  16. Horvath, J. C., Forte, J. D., & Carter, O. (2015a). Evidence that transcranial direct current stimulation (tDCS) generates little-to-no reliable neurophysiologic effect beyond MEP amplitude modulation in healthy human subjects: a systematic review. Neuropsychologia., 66, 213–236.PubMedGoogle Scholar
  17. Horvath, J. C., Forte, J. D., & Carter, O. (2015b). Quantitative review finds no evidence of cognitive effects in healthy populations from single-session transcranial direct current stimulation (tDCS). Brain Stimulation, 8(3), 535–550.PubMedGoogle Scholar
  18. Hoy, K. E., Emonson, M. R. L., Arnold, S. L., Thomson, R. H., Daskalakis, Z. J., & Fitzgerald, P. B. (2013). Testing the limits: Investigating the effect of tDCS dose on working memory enhancement in healthy controls. Neuropsychologia., 51(9), 1777–1784.PubMedGoogle Scholar
  19. Jacobson, L., Ezra, A., Berger, U., & Lavidor, M. (2012). Modulating oscillatory brain activity correlates of behavioral inhibition using transcranial direct current stimulation. Clinical Neurophysiology, 123(5), 979–984.PubMedGoogle Scholar
  20. JASP Team. (2019). JASP (Version 0.9.2) [Computer software]. Retrieved from https://jasp-stats.org/.
  21. Jeffreys, H. (1962). Theory of probability (3rd ed.). Oxford: Oxford University Press.Google Scholar
  22. Jensen, O., & Tesche, C. D. (2002). Frontal theta activity in humans increases with memory load in a working memory task. The European Journal of Neuroscience, 15, 1395–1399.PubMedGoogle Scholar
  23. Keeser, D., Padberg, F., Reisinger, E., Pogarell, O., Kirsch, V., Palm, U., et al. (2011). Prefrontal direct current stimulation modulates resting EEG and event-related potentials in healthy subjects: a standardized low resolution tomography (sLORETA) study. Neuroimage., 55(2), 644–657.PubMedGoogle Scholar
  24. Klimesch, W., Freunberger, R., & Sauseng, P. (2010). Oscillatory mechanisms of process binding in memory. Neuroscience and Biobehavioral Reviews, 34(7), 1002–1014.PubMedGoogle Scholar
  25. Mancuso, L. E., Ilieva, I. P., Hamilton, R., & Farah, M. J. (2016). Does transcranial direct current stimulation improve healthy working memory ?: a meta- analytic review. Journal of Cognitive Neuroscience, 28(8), 1063–1089.PubMedGoogle Scholar
  26. Maurer, U., Brem, S., Liechti, M., Maurizio, S., Michels, L., & Brandeis, D. (2015). Frontal midline theta reflects individual task performance in a working memory task. Brain Topography, 28, 127–134.PubMedGoogle Scholar
  27. Miller, J., Berger, B., & Sauseng, P. (2015). Anodal transcranial direct current stimulation (tDCS) increases frontal-midline theta activity in the human EEG: a preliminary investigation of non-invasive stimulation. Neuroscience Letters, 588, 114–119.PubMedGoogle Scholar
  28. Minarik, T., Berger, B., Althaus, L., Bader, V., Biebl, B., Brotzeller, F., et al. (2016). The importance of sample size for reproducibility of tDCS effects. Frontiers in Human Neuroscience, 10(September), 1–5.Google Scholar
  29. Nitsche, M. A., & Paulus, W. (2011). Transcranial direct current stimulation - Update 2011. Restorative Neurology and Neuroscience, 29(6), 463–492.PubMedGoogle Scholar
  30. Nitsche, M. A., Cohen, L. G., Wassermann, E. M., Priori, A., Lang, N., Antal, A., et al. (2008). Transcranial direct current stimulation: state of the art 2008. Brain Stimulation, 1(3), 206–223.PubMedGoogle Scholar
  31. Oswald, W. D., & Roth, E. (1978). Der Zahlen-Verbindungs-test (ZVT). Ein sprachfreier Intelligenz-Test zur Messung der “kognitiven Leistungsgeschwindigkeit” (2nd ed.). Göttingen: Hogrefe.Google Scholar
  32. Price, A. R., & Hamilton, R. H. (2015). A re-evaluation of the cognitive effects from single-session transcranial direct current stimulation. Brain Stimulation, 8(3), 663–665.PubMedGoogle Scholar
  33. Rouder, J. N., Morey, R. D., & Iverson, G. J. (2009). Bayesian t tests for accepting and rejecting the null hypothesis. Psychonomic Bulletin, 16(May), 225–237.Google Scholar
  34. Rouder, J. N., Morey, R. D., Speckman, P. L., & Province, J. M. (2012). Default Bayes factors for ANOVA designs. Journal of Mathematical Psychology, 56(5), 356–374.Google Scholar
  35. Salthouse, T. A. (2011). Cognitive correlates of cross-sectional differences and longitudinal changes in trail making performance. Journal of Clinical and Experimental Neuropsychology, 33(2), 242–248.PubMedGoogle Scholar
  36. Sauseng, P., Klimesch, W., Doppelmayr, M., Hanslmayr, S., Schabus, M., & Gruber, W. R. (2004). Theta coupling in the human electroencephalogram during a working memory task. Neuroscience Letters, 354(2), 123–126.PubMedGoogle Scholar
  37. Sauseng, P., Klimesch, W., Schabus, M., & Doppelmayr, M. (2005). Fronto-parietal EEG coherence in theta and upper alpha reflect central executive functions of working memory. International Journal of Psychophysiology, 57(2), 97–103.PubMedGoogle Scholar
  38. Sauseng, P., Hoppe, J., Klimesch, W., Gerloff, C., & Hummel, F. C. (2007). Dissociation of sustained attention from central executive functions: local activity and interregional connectivity in the theta range. The European Journal of Neuroscience, 25(2), 587–593.PubMedGoogle Scholar
  39. Sauseng, P., Griesmayr, B., Freunberger, R., & Klimesch, W. (2010). Control mechanisms in working memory: a possible function of EEG theta oscillations. Neuroscience and Biobehavioral Reviews, 34(7), 1015–1022.PubMedGoogle Scholar
  40. Scharinger, C., Soutschek, A., Schubert, T., & Gerjets, P. (2017). Comparison of the working memory load in N-Back and working memory span tasks by means of EEG frequency band power and P300 amplitude. Frontiers in Human Neuroscience, 11(January), 1–19.Google Scholar
  41. Shin, Y. I., Foerster, Á., & Nitsche, M. A. (2015). Transcranial direct current stimulation (tDCS) - application in neuropsychology. Neuropsychologia., 69, 154–175.PubMedGoogle Scholar
  42. Tschentscher, N., Mitchell, X. D., & Duncan, X. J. (2017). Fluid intelligence predicts novel rule implementation in a distributed Frontoparietal control network. The Journal of Neuroscience, 37(18), 4841–4847.PubMedPubMedCentralGoogle Scholar
  43. Vernon, P. A. (1993). Der Zahlen-Verbindungs-test and other trail-making correlates of general intelligence. Personality and Individual Differences, 14(1), 35–40.Google Scholar
  44. Zaehle, T., Sandmann, P., Thorne, J. D., Jancke, L., & Herrmann, C. S. (2011). Transcranial direct current stimulation of the prefrontal cortex modulates working memory performance: combined behavioural and electrophysiological evidence. BMC Neuroscience, 12(1), 2.PubMedPubMedCentralGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Elisabeth V. C. Friedrich
    • 1
  • Barbara Berger
    • 1
    • 2
  • Tamas Minarik
    • 1
    • 2
  • Doris Schmid
    • 1
  • Charline Peylo
    • 1
  • Paul Sauseng
    • 1
    Email author
  1. 1.Department of Psychology, Research Unit Biological PsychologyLudwig-Maximilians-University MunichMunichGermany
  2. 2.School of Psychology, Centre for Human Brain HealthUniversity of BirminghamBirminghamUK

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