Analysis of MEG Signals for Selective Arithmetic Tasks

  • Graham PeytonEmail author
  • David M. Rubin
  • Adam Pantanowitz
  • Amir Kleks
  • Mina Teicher
Conference paper
Part of the IFMBE Proceedings book series (IFMBE, volume 57)


In this study, magnetoencephalography (MEG) data were recorded as subjects carried out a basic numerical task: deciding whether a number is even or odd. Signal processing techniques were applied to the MEG data so as to characterise the spatial and temporal dynamics of the brain during the decision-making process. Event-related fields (ERFs) were found by averaging all the trials in the time domain. Induced potentials or oscillatory rhythms were found by averaging the time-frequency representations (TFRs) for all the trials. The TFRs were found using the Wavelet transform. The results show that typical ERF components are present just after the onset of the stimulus. N100, P200 and N200 waveforms indicate that the brain carries out higher-order perceptual processing modulated by attention, and that memory may play a critical role in parity selection. TFRs show beta-band synchronisation as the individual concentrates on the mental task, followed by desynchronisation as the motor response is carried out. Activity is pronounced in the left general interpretive area (Wernicke’s area) with a latency of around 610 ms.


Event-related fields Magnetoencephalography Time-frequency representations Parity selection 


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Graham Peyton
    • 1
    Email author
  • David M. Rubin
    • 1
  • Adam Pantanowitz
    • 1
  • Amir Kleks
    • 2
  • Mina Teicher
    • 3
  1. 1.Biomedical Engineering Research Group, School of Electrical and Information EngineeringUniversity of the WitwatersrandJohannesburgSouth Africa
  2. 2.Gonda Brain Research CenterBar-Ilan UniversityRamat-GanIsrael
  3. 3.Department of MathematicsBar-Ilan UniversityRamat-GanIsrael

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