Journal of Medical and Biological Engineering

, Volume 37, Issue 2, pp 220–229 | Cite as

EEG Synchronizations Length During Meditation

  • Jakub KopalEmail author
  • Oldřich Vyšata
  • Jan Burian
  • Martin Schätz
  • Aleš Procházka
  • Martin Vališ
Original Article


The dynamic structure of the EEG signal is characterized by segments of synchronization and desynchronization. In this paper, the frequency and duration of these segments were monitored during calm meditation and insight meditation in experienced and naive meditators. A newly developed methodology based on complex continuous wavelet coherence was used to estimate these parameters. The durations highly depend on frequency band and vary from 60 ms to 250 ms. A shorter duration and a lower frequency of synchronization were found for experienced meditators during both types of meditations for the real and the imaginary parts of the complex continuous wavelet coherence. The greatest duration differences were in the gamma band, which may be associated with handling attention during meditation, whereas the differences in the alpha band were most significant for frequency. Combining the two parameters resulted in the total duration of the synchronization, which has discriminative accuracy of up to 100% and appears to be a sensitive parameter of the length of training of meditators.


Calm meditation Continuous complex wavelet coherence EEG synchronization Insight meditation 



Continuous wavelet transform


Wavelet cross spectrum


Complex continuous wavelet coherence


Receiver operating characteristic




Finite impulse response



This work was supported by the grant MH CZ- DRO. Faculty Hospital in Hradec Kralove (long-term organization development plan) (UHHK, 00179906) and by the grant PRVOUK: P37/08.

Compliance with Ethical Standard

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

JK, OV, AP participated in the design of the study and performed the statistical analysis. Data were collected and analyzed by the investigators JK, JB, OV. OV, AP, MV conceived of the study, and participated in its design and helped to draft the manuscript. All authors read and approved the final manuscript.

Supplementary material

40846_2017_219_MOESM1_ESM.docx (16 kb)
Supplementary material 1 (DOCX 15 kb)


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Copyright information

© Taiwanese Society of Biomedical Engineering 2017

Authors and Affiliations

  • Jakub Kopal
    • 1
    Email author
  • Oldřich Vyšata
    • 1
    • 2
  • Jan Burian
    • 3
  • Martin Schätz
    • 1
  • Aleš Procházka
    • 1
  • Martin Vališ
    • 2
  1. 1.Department of Computing and Control EngineeringUniversity of Chemistry and TechnologyPrague 6Czech Republic
  2. 2.Department of Neurology, Faculty of Medicine in Hradec KraloveCharles UniversityHradec KraloveCzech Republic
  3. 3.Faculty of Informatics and StatisticsUniversity of Economics PraguePrague 3Czech Republic

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