# Approaching Electroencephalographic Pathological Spikes in Terms of Solitons
## 7 Conclusions
Potential detrimental solitons correlated with medical conditions might be countered and neutralized in various ways. Since solitons are produced by a delicate balance between nonlinear and dissipative forces like viscosity, a pharmacologically induced modification of the brain viscosity might lead to the derangement of pathological solitons. Further, solitons display peculiar physical features like non-sinusoidal waves that could be theoretically manipulated by focal electrical brain stimulation induced by external magnetic fields, namely, by transcranial magnetic stimulation (TMS) [62; 63]. In pathological states, the ordinary EEG oscillations deviate from the norm. In this case, our model of nervous solitons based on Schrodinger-like equations predicts that pathological spikes could be correlated with changes in the anatomical/functional location of the electric sources. Figure 3 provides a proof-of-concept example of brain EEG waves treated in terms of the Schrodinger equation. In the healthy brain, the energy sources are arranged in a regular order along the straight line connecting two scalp electrodes (Figure 3A). This generates a regular wave with well-defined periodicity and rhythm. When a disease occurs, e.g., an epileptic focus, one of the energy sources turns off its location on the straight line (Figure 3B). This divergence perturbs the wave profile: even slight changes in the location of energy sources can vary the potential, leading to waves with fully different shapes. To restore the healthy wave, an appropriately located external current could be given via TMS to counteract the effects of the displaced energy source (Figure 3C). Note that the profile wave in Figure 3 is drawn from the classical Schrodinger equation that holds just for microscopic systems subject to the laws of quantum mechanics. Nevertheless, the example can be generalized to macroscopic systems like EEG traces when considering NLSE instead of the classical Schrodinger equation. Therefore, artificial manipulation of harmful solitons in the nervous tissue can be achieved by superimposing TMS external currents to counteract the pathological electric waves. This might have consequences for medical treatment. For instance, the proper external current might contribute to modify the harmful solitons produced during epileptic discharge, bringing healing to the convulsive symptoms. The possible relationships between solitary waves and brain activities pave the way to novel lines of research. We focused on the spikes extracted from EEG traces, but the universe of the discourse could also be extended to the oscillations detected by other experimental procedures like fMRI and local field potential electrophysiology. When nonlinear effects occur in silica optical fibers, the momentum and the medium dispersion might coincide. This generates a \"phase matching\" that allows solitons to emit a special kind of low-intensity radiation called resonant radiation [33]. It could be speculated that this radiation could be found also in EEG traces. The property of solitons to interact with each other in a nonlinear medium suggests that they could also be analyzed in terms of elastically colliding particles that do not interact with each other and do not perturb the wave [46, 64]. When the soliton propagates through the medium, the particles are accelerated until the wave has left the region. After the interaction, the particles become motionless again, but their positions have shifted. The particles' single trajectories are influenced only by wave velocity, while their movement is governed by the current flow. This suggests that solitons at the interface of two biological fluid mediums might be useful to move or mix particles, contributing to the intra- and extra-cellular transport mechanisms. In summation, research concerning relationships and interactions between solitons and the electric waves produced by the central nervous system still requires attention, but the premises are so promising that the field would be worth exploring.