Table 1 A review of the researches on transmission of light in nerve fiber.
From: Simulation of nerve fiber based on anti-resonant reflecting optical waveguide
Mechanism | Source | Size | Optical imperfections | Results | Ref |
|---|---|---|---|---|---|
Myelin sheath as a waveguide of biophotons | Biophoton @ Infrared and visible | g-ratio = 0.6 Laxon = 100 µm Daxon = 0.6–3 µm | Bending Variation of cross section of myelinated axon | The myelinated axon as a waveguide guides photons only in myelin sheath Presence of bending, varying cross-sectional area and increasing the diameter of the nerve fiber, reduces light transmission | |
Ranvier node as Bio-Nano antennas | Eectromagnetic radiation @ Infrared and visible | g-ratio = 0.78 Laxon = 100 µm Daxon = 0.57 µm | NR NR as antenna | NR of myelinated axons as a nanoantenna array system Radiate optical waves propagating through the myelinated axon Myelinated axon acts as waveguide | |
Nerve fibers as a waveguide | Biophoton / external light source @ visible | g-ratio = 0.7 Laxon = 27 µm Daxon = 0.4 µm | NR demyelination Myelin as lossy and lossless media | Axon acts as a waveguide Assessed myelin sheath as lossless and lossy model Propose a mechanism based on nanoparticles to repair photon transmission inside demyelinated nerve fibers | |
Label-free nanoscale optical metrology on Myelinated axons in vivo | Spectrally scanned white-light laser @ visible | Daxon = 0.5 µm Myelin thickness: 18-48 nm | Myelin as Multi-layered NR Variation of axon size Variation of number of myelin layers | The Multi-layered features of myelin act as a thin film around the axon fibers Spectral reflectometry (SpeRe) is able to nanoscale imaging of myelinated axons in their natural living state SpeRe can be used to investigate osmotic swelling and traumatic brain injury by determining the degree of myelination, wavenumber period for axon diameter, and spectral shift for myelin swelling | |
Myelin as coil inductor and cell membrane as a piezoelectric | Two voltage sources | Daxon = 1.2 µm Myelin thickness = 10 nm spacing between the two layers = 4 nm with 15 rounds | Myelin as Multi-layered NR | Myelin sheath acts as a coil inductor to generate a magnetic field The coil inductance of myelin and the piezoelectric effect of cell membrane explains the measured mechanical wave and the spiraling of the myelin sheaths in neurons | |
Müller cells act as a waveguide to improve day vision | Broad spectral source @ Visible | Müller cell length: 130 nm proximal cup of Müller cell :12 µm in diameter | Not available (N/A) | The Müller cell, performing as a wavelength-dependent optical fiber In Müller cells, the wavelength of incident light is sorted so that the wavelengths suitable for cones are directed to the cones, while those are more suitable for rods leak outside the Müller cells and reach the surrounding rods | |
Mitochondria as a waveguide | Electromagnetic radiation @ Visible | N/A | N/A | Microtubules and mitochondria function as optical waveguides due to their higher refractive index compared to cytoplasm Mitochondria as an optical multi-layer system Mitochondria emit chemiluminescent light, and light can be guided along with the mitochondrial network | |
Nerve Fiber as an Anti-Resonant Reflecting Optical Waveguide | External light source @ visible | G-ratio = 0.7 Laxon = 27 µm Daxon = 0.4 µm | Bending NR | The myelinated axon as a waveguide Beams propagation in both axon and myelin sheath, depending on the source launching to myelinated axon In anti-resonant condition the myelin acts as Fabry-Pérot and light propagate in core In resonance wavelength if light launches to myelin, total internal reflection will happen | This paper |
