Plasma Brain Dynamics (PBD): A Mechanism for EEG Waves Under Human Consciousness

TL;DR

This paper models EEG wave formation and propagation as plasma-like solitary waves in the brain, extending plasma physics equations to explain different EEG wave types and their dependence on brain electromagnetic and ionic conditions.

Contribution

It introduces a plasma physics-based model for EEG waves, extending Vlasov-Maxwell equations to a two-fluid nonlinear solitary wave framework for the first time.

Findings

EEG wave packets depend on electric/magnetic fields and ionic conditions.

Group-1 waves involve ion-acoustic, lower-hybrid, and ion-cyclotron modes.

Group-2 waves are within the ion-acoustic band with various envelope shapes.

Abstract

EEG signals are records of nonlinear solitary waves in human brains. The waves have several types (e.g., a, b, g, q, d) in response to different levels of consciousness. They are classified into two groups: Group-1 consists of complex storm-like waves (a, b, and g); Group-2 is composed of simple quasilinear waves (q and d). In order to elucidate the mechanism of EEG wave formation and propagation, this paper extends the Vlasov-Maxwell equations of Plasma Brain Dynamics (PBD) to a set of two-fluid, self-similar, nonlinear solitary wave equations. Numerical simulations are performed for different EEG signals. Main results include: (1) The excitation and propagation of the EEG wave packets are dependent of electric and magnetic fields, brain aqua-ions, electron and ion temperatures, masses, and their initial fluid speeds; (2) Group-1 complex waves contain three ingredients: the high-frequency ion-acoustic (IA) mode, the intermediate-frequency lower-hybrid (LH) mode, and the low-frequency ion-cyclotron (IC) mode; (3) Group-2 simple waves fall within the IA band, featured by one or a combination of the three envelopes: sinusoidal, sawtooth, and spiky/bipolar. The study proposes an alternative model to Quantum Brain Dynamics (QBD) by suggesting that the formation and propagation of the nonlinear solitary EEG waves in the brain have the same mechanism as that of the waves in space plasmas