title: A study of composite electrode-tissue impedance.
abstract: Electrical impedance tomography has been used in the medical environment for many years. Recently it has been used for brain function imaging. This type of technology uses a large number of electrodes on the scalp, examples in the literature ranging from 8 to 64. In this paper, the composite impedance of the electrode in contact with tissue is investigated. An experimental method has been developed to enable the use of a commercial impedance analyzer in compliance with medical safety standards. The magnitude and long-term stability of the composite impedance of the electrode-tissue system is found to be greatly dependent on the type of electrodes used.
authors.affiliation: School of Electrical Engineering and Electronics, University of Manchester, PO Box 88, M60 1QD, UK. Rebecca.Robinson@postgrad.manchester.ac.uk
authors.forename: R L
authors.initials: RL
authors.lastname: Robinson
authors.forename: J L
authors.initials: JL
authors.lastname: Davidson
authors.forename: P
authors.initials: P
authors.lastname: Wright
authors.forename: C J D
authors.initials: CJ
authors.lastname: Pomfrett
authors.forename: H
authors.initials: H
authors.lastname: McCann
mesh_terms: D003198:Computer Simulation; D004553:Electric Conductivity; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008954:Models, Biological; D010992:Plethysmography, Impedance / Q000295:instrumentation* / Q000379:methods*