Numerical Assessment of EEG Electrode Artifacts during EMF Exposure in Human Provocation Studies

The paper presents the numerical evaluation of the electroencephalogram (EEG) electrode artifacts that are caused during exposure to electromagnetic fields (EMF), in volunteers study. The scope of the study is to differentially present the electromagnetic (EM) power absorption and local Specific Absorption Rate (SAR) distribution, with and without the electrodes. Versions of two basic exposure scenarios are evaluated: flat layered tissue phantom and anatomical head model exposed to plane wave or patch antenna radiation at operating frequency of 1966 MHz. Finite Difference Time Domain (FDTD) method is used in order to model the computational domain. E-field distributions and SAR values are calculated. The electromagnetic power absorption by the brain tissues is correlated with the presence of the EEG electrodes and the relative positioning of their leads. Results conclude in significant alternations in EM power absorption, E-field and SAR distributions, due to the co-polarization between the leads and the E-field. Concerning the realistic scenario, the presence of 32 electrodes and their leads enhances (11% without and 12.3% with electric contact) the psSAR10g, comparing to the reference simulation.