Slow Theta tACS of the Right Parietal Cortex Enhances Contralateral Visual Working Memory Capacity

  • Monika Bender
  • Vincenzo Romei
  • Paul SausengEmail author
Brief Communication


Recent research suggests alteration of visual working memory capacity by modulation of parietal theta frequency via transcranial alternating current stimulation (tACS). However, it remains to be clarified whether this effect is partly driven by co-stimulation of prefrontal cortex and subcortical structures. It was hypothesized that focal tACS over the parietal lobe without additional prefrontal or subcortical stimulation should lead to similar effects as reported in the literature. Healthy, young participants were tested on a visual working memory paradigm while receiving either focal parietal tACS at 4 Hz, at 7 Hz or sham stimulation. Focal right posterior 4 Hz tACS led to increased working memory capacity strictly for the visual hemifield contralateral to stimulation. Exclusive stimulation of posterior cortex by 4 Hz tACS replicates effects recently reported in literature, confirming that stimulation of the prefrontal cortex or subcortical structures are not a primary driver of these observations.


Focal tACS Modulation of brain frequencies Nesting of oscillations Theta:gamma coupling 



This research was supported by the Deutsche Forschungsgemeinschaft DFG (Grant SA 1872/2-1 to PS) and the BIAL Foundation (Grant Number 204/2018 to VR).

Supplementary material

10548_2019_702_MOESM1_ESM.docx (81 kb)
Supplementary material 1 (DOCX 80 KB)


  1. Antonenko D, Faxel M, Grittner U et al (2016) Effects of transcranial alternating current stimulation on cognitive functions in healthy young and older adults. Neural Plast 2016:4274127. CrossRefGoogle Scholar
  2. Chhatbar PY, Kautz SA, Takacs I et al (2018) Evidence of transcranial direct current stimulation-generated electric fields at subthalamic level in human brain in vivo. Brain Stimulat 11:727–733. CrossRefGoogle Scholar
  3. Cowan N (2001) The magical number 4 in short-term memory: a reconsideration of mental storage capacity. Behav Brain Sci 24:87–114; discussion 114–185CrossRefGoogle Scholar
  4. Fresnoza S, Christova M, Feil T et al (2018) The effects of transcranial alternating current stimulation (tACS) at individual alpha peak frequency (iAPF) on motor cortex excitability in young and elderly adults. Exp Brain Res 236:2573–2588. CrossRefGoogle Scholar
  5. Jensen O, Lisman JE (1996) Novel lists of 7+/-2 known items can be reliably stored in an oscillatory short-term memory network: interaction with long-term memory. Learn Mem Cold Spring Harb N 3:257–263CrossRefGoogle Scholar
  6. Jensen O, Lisman JE (1998) An oscillatory short-term memory buffer model can account for data on the Sternberg task. J Neurosci Off J Soc Neurosci 18:10688–10699CrossRefGoogle Scholar
  7. Lisman JE, Idiart MA (1995) Storage of 7 +/- 2 short-term memories in oscillatory subcycles. Science 267:1512–1515CrossRefGoogle Scholar
  8. Lisman JE, Jensen O (2013) The θ-γ neural code. Neuron 77:1002–1016. CrossRefGoogle Scholar
  9. Miranda PC, Mekonnen A, Salvador R, Ruffini G (2013) The electric field in the cortex during transcranial current stimulation. NeuroImage 70:48–58. CrossRefGoogle Scholar
  10. Rufener KS, Oechslin MS, Zaehle T, Meyer M (2016) Transcranial Alternating Current Stimulation (tACS) differentially modulates speech perception in young and older adults. Brain Stimulat 9:560–565. CrossRefGoogle Scholar
  11. Sauseng P, Peylo C, Biel AL et al (2018) Does cross-frequency phase coupling of oscillatory brain activity contribute to a better understanding of visual working memory? Br J Psychol Lond Engl Google Scholar
  12. Tseng P, Iu K-C, Juan C-H (2018) The critical role of phase difference in theta oscillation between bilateral parietal cortices for visuospatial working memory. Sci Rep 8:349. CrossRefGoogle Scholar
  13. Turi Z, Alekseichuk I, Paulus W (2018) On ways to overcome the magical capacity limit of working memory. PLoS Biol 16:e2005867. CrossRefGoogle Scholar
  14. Violante IR, Li LM, Carmichael DW et al (2017) Externally induced frontoparietal synchronization modulates network dynamics and enhances working memory performance. eLife Google Scholar
  15. Vosskuhl J, Huster RJ, Herrmann CS (2015) Increase in short-term memory capacity induced by down-regulating individual theta frequency via transcranial alternating current stimulation. Front Hum Neurosci 9:257. CrossRefGoogle Scholar
  16. Wolinski N, Cooper NR, Sauseng P, Romei V (2018) The speed of parietal theta frequency drives visuospatial working memory capacity. PLoS Biol 16:e2005348CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of PsychologyLudwig-Maximilians-Universität MünchenMunichGermany
  2. 2.Dipartimento di PsicologiaUniversità di BolognaCesenaItaly

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