MIDIT OFD CATS Modelling, Nonlinear Dynamics Optics and Fluid Dynamics Chaos and Turbulence Studies and Irreversible Thermodynamics Risø National Laboratory Niels Bohr Institute and Technical University of Denmark Building 128 Department of Chemistry Building 321 P.O. Box 49 University of Copenhagen DK-2800 Lyngby DK-4000 Roskilde DK-2100 Copenhagen Ø Denmark Denmark Denmark
by Morten Nordahn
NKT Research Center
Monday April 19, 1999, 15:15 - 15:45 h
at MIDIT, IMM Building 305, room 027
Abstract: As a part of the mechanism behind the propagating compound action potential in peripheral nerves, ionic currents induce a weak magnetic field (less than 200 fT at the surface of the skin), which can be measured by highly sensitive devices. A non-invasive measuring technique offers a promising alternative to the existing highly invasive techniques used in Danish hospitals today, which measure the bioelectric fields generated by the propagating action potential by use of painful needle electrodes. In this talk, a brief introduction to the generation of biomagnetic fields in peripheral nerves will is given. Furthermore, biomagnetic measurements on human peripheral nerves will be presented. The measurements have been carried out using a low-temperature, low-noise, 49-channel SQUID (Superconducting QUantum Interference Device) sensor array system. Methods of extracting the weak signal are introduced, and the results are discussed.