Study of the Electromagnetic Field of Transcranial Magnetic Stimulation Based on the Real Head Model

This paper presents the application of finite element method in analysis of the electromagnetic field within real head model exposed to a time varying magnetic field produced by the circuit-driving loop. To analyze the electromagnetic field under Transcranial Magnetic Stimulation precisely and display the stimulating effect of the loops in different geometrical forms, a 3-D real head model reconstructed from the CT Images is used to simulate the head. Based on the practical circuit of the magnetic stimulating instrument, the cerebral electromagnetic field produced by the loops of 4 different forms is analyzed with their electromagnetic performance evaluated. The work can provide the academic and practical basis for further study upon Transcranial Magnetic Stimulation and developing more complicated loop or loop array.

[1]  R J Ilmoniemi,et al.  Transcranial magnetic stimulation as a tool for cognitive studies. , 2001, Scandinavian journal of psychology.

[2]  G Cerri,et al.  An accurate 3-D model for magnetic stimulation of the brain cortex. , 1995, Journal of medical engineering & technology.

[3]  Markus Zahn,et al.  Three-dimensional head model Simulation of transcranial magnetic stimulation , 2004, IEEE Transactions on Biomedical Engineering.

[4]  Yong Chen,et al.  The Optimal Design of Magnetic Coil in Transcranial Magnetic Stimulation , 2005, 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference.

[5]  G. A. Mouchawar,et al.  Magnetic stimulation of excitable tissue: calculation of induced eddy-currents with a three-dimensional finite-element model , 1993 .

[6]  Solomon R. Eisenberg,et al.  A three-dimensional finite element method for computing magnetically induced currents in tissues , 1994 .

[7]  S. Ueno,et al.  Magnetic Stimulation of the Human Brain , 1992, Annals of the New York Academy of Sciences.

[8]  Mikael Persson,et al.  Computation of electric and magnetic stimulation in human head using the 3-D impedance method , 2003, IEEE Trans. Biomed. Eng..

[9]  A. Barker.  An Introduction to the Basic Principles of Magnetic Nerve Stimulation , 1991, Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society.

[10]  J. Rothwell,et al.  Functional Connectivity of Human Premotor and Motor Cortex Explored with Repetitive Transcranial Magnetic Stimulation , 2002, The Journal of Neuroscience.

[11]  Seppo Kähkönen,et al.  Transcranial Magnetic Stimulation: Applications for Neuropsychopharmacology , 2004, Journal of psychopharmacology.

[12]  M Hallett,et al.  A theoretical calculation of the electric field induced in the cortex during magnetic stimulation. , 1991, Electroencephalography and clinical neurophysiology.