Experimental Brain Research

, Volume 231, Issue 4, pp 495–500 | Cite as

Spontaneous EEG fluctuations determine the readiness potential: is preconscious brain activation a preparation process to move?

  • Han-Gue Jo
  • Thilo Hinterberger
  • Marc Wittmann
  • Tilmann Lhündrup Borghardt
  • Stefan Schmidt
Research Article


It has been repeatedly shown that specific brain activity related to planning movement develops before the conscious intention to act. This empirical finding strongly challenges the notion of free will. Here, we demonstrate that in the Libet experiment, spontaneous fluctuations of the slow electro-cortical potentials (SCPs) account for a significant fraction of the readiness potential (RP). The individual potential shifts preceding self-initiated movements were classified as showing a negative or positive shift. The negative and positive potential shifts were analyzed in a self-initiated movement condition and in a no-movement condition. Comparing the potential shifts between both conditions, we observed no differences in the early part of the potential. This reveals that the apparently negative RP emerges through an unequal ratio of negative and positive potential shifts. These results suggest that ongoing negative shifts of the SCPs facilitate self-initiated movement but are not related to processes underlying preparation or decision to act.


Free will Intention to move Libet experiment Slow cortical potential Readiness potential 

Supplementary material

221_2013_3713_MOESM1_ESM.pdf (142 kb)
Supplementary material 1 (PDF 142 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Han-Gue Jo
    • 1
    • 2
  • Thilo Hinterberger
    • 3
  • Marc Wittmann
    • 4
  • Tilmann Lhündrup Borghardt
    • 1
  • Stefan Schmidt
    • 1
    • 2
  1. 1.Department of Psychosomatic MedicineUniversity Medical Center FreiburgFreiburgGermany
  2. 2.Institute for Transcultural Health StudiesEuropean University ViadrinaFrankfurt (Oder)Germany
  3. 3.Research Section of Applied Consciousness Sciences, Department of Psychosomatic MedicineUniversity Medical Center RegensburgRegensburgGermany
  4. 4.Institute for Frontier Areas of Psychology and Mental HealthFreiburgGermany

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