Engineering Photonic Transmission Inside Brain Nerve Fibers

Electrical signaling is known as the means for inter-cellular connectivity among neural cells. However, there are some indications that optical phenomena can occur in the neuronal cells based on biochemical processes in intra-or extracellular reactions. Also, external optical signals can be used to manipulate engineered neural cells for performing key functions. Motivated by these, this paper establishes a framework on photon transmission inside nerve fiber using optical properties of the nerve tissues to study photonic signaling. We use the same framework to analyze and propose mitigation using nanoparticles for demyelinated nerve channels- a potential cause for certain brain disorders like Alzheimer's disease. Our study assumes photons are available. The proposed framework for photonic signaling across nerve fibers uses an analytical model of a nerve fiber's segment that consists of physical factors, including size, Ranvier node presence, and interconnected segments. The demyelination effect on the nerve channel is evaluated by numerical electromagnetic computations. On this basis, photonic transmittance of a defected nerve segment is calculated, while demyelination takes place in different locations, lengths, and depths across the nerve segment. To repair the demyelination and enhance the transmittance of the demyelinated axon, we have performed analysis on nanoparticles such as silicon and silica quantum dots, gold nanoparticles, and gold/silica core-shell nanoparticles. Our computational models show that nanoparticles' presence improves the optical properties of nerve configuration that indicate photons can be transmitted in the axonal routes of demyelinated channels.