Effect of peripheral nerve action currents on magnetic resonance imaging.
Many researchers have attempted to detect neural currents directly using magnetic resonance imaging (MRI). The action currents of a peripheral nerve create their own magnetic field that can cause the phase of the spins to change. Our goal in this paper is to use the measured magnetic field of a nerve to estimate the resulting phase shift in the magnetic resonance signal. We examine three cases: the squid giant axon, the frog sciatic nerve, and the human median nerve. In each case, the phase shift is much less than one degree, and will be very difficult to measure with current technology.
Wijesinghe
Ranjith
R
Department of Physics and Astronomy, Ball State University, Muncie, Indiana, USA. rswijesinghe@bsu.edu
Roth
Bradley J
BJ
D000200:Action Potentials; D000465:Algorithms; D000818:Animals; D001001:Anura; D001369:Axons / Q000473:pathology*; D001698:Biomedical Engineering / Q000379:methods; D049832:Decapodiformes; D004867:Equipment Design; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008475:Median Nerve / Q000473:pathology*; D010525:Peripheral Nerves / Q000378:metabolism / Q000473:pathology*; D012584:Sciatic Nerve / Q000473:pathology*; D012815:Signal Processing, Computer-Assisted