Theoretically modeling oscillations and waves (EEG and MEG signals) of the brain neuronal fluids and extracellular fluids, using plasma hydrodynamics

Abstract

Introduction: Ionic oscillations and waves of the brain neurons are mostly analyzed and recorded by EEG (electroencephalography) and (or) MEG (magnetoencephalography). In principle EEG and MEG signals arise from the same neuronal sources. The traditional models of EEG and MEG do not involve natural excitations and attenuations, encodings (decodings), displacement currents of the brain neuronal electromagnetic signals, nor active pumps and passive channels of biological ions. Besides, we have not found any published research at an ionic level to theoretically describe the mechanisms how oscillations and waves of the brain neuronal fluids and extracellular fluids are excited, attenuated and maintained in the both natural and forced modes. Methods and Results: We introduce the plasma physics into brain theory; based on plasma hydrodynamic equations and published data of the brain or neuron sciences and molecular biology, at an ionic level, we model the mechanisms of the complete procedures of excitations, attenuations, propagations (oscillations and waves) of the brain neuronal fluids and extracellular fluids in the both natural and forced modes; our models include active pumps and passive channels of biological ions. Moreover, we also elucidate frequency and amplitude modulations (encodings), displacement currents, as well as effective values of the alternating electric current densities, electric and magnetic fields and voltages, based on the modeling results of the brain neuronal and extracellular plasma waves (oscillations). Conclusion: Our modeling results are qualitatively consistent with the published data of brain neuroscience as well as EEG and MEG.