Abstract
In magnetoencephalography (MEG), the magnetic fields created by electrical activity in the brain are measured on the surface of the skull. To determine the location of the activity, the measured field is fit to a parameterized source generator model by minimizing chi-square. In the case of a current dipole model, the parameters computed by the fitting procedure are the location and orientation of the dipole. For current dipoles and other nonlinear source models, the fit is performed by an iterative least squares procedure such as the Levenberg-Marquardt algorithm (Press 1986). Once the fit has been computed, analysis of the resulting value of chi-square can determine whether the assumed source model is adequate to account for the measurements. If the source model is adequate, then the effect of measurement error on the fitted model parameters must be analyzed.
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© 1989 Plenum Press, New York
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Medvick, P.A., Lewis, P.S., Aine, C., Flynn, E.R. (1989). Monte Carlo Analysis of Localization Errors in Magnetoencephalography. In: Williamson, S.J., Hoke, M., Stroink, G., Kotani, M. (eds) Advances in Biomagnetism. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0581-1_118
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DOI: https://doi.org/10.1007/978-1-4613-0581-1_118
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