title: Global optimization in the localization of neuromagnetic sources.
abstract: The locations of active brain areas can be estimated from the magnetic field produced by the neural current sources. In many cases, the actual current distribution can be modeled with a set of stationary current dipoles with time-varying amplitudes. This work studies global optimization methods that find the minimum of the least-squares error function of the current dipole estimation problem. Three different global optimization methods were investigated: clustering method, simulated annealing, and genetic algorithms. In simulation studies, the genetic algorithm was the most effective method. The methods were also applied to analysis of actual measurement data.
authors.affiliation: Low Temperature Laboratory, Helsinki University of Technology, Finland. Kimmo.Uutela@hut.fi
authors.forename: K
authors.initials: K
authors.lastname: Uutela
authors.forename: M
authors.initials: M
authors.lastname: Hämäläinen
authors.forename: R
authors.initials: R
authors.lastname: Salmelin
mesh_terms: D000465:Algorithms; D005072:Evoked Potentials, Auditory; D006801:Humans; D007807:Language Tests; D016018:Least-Squares Analysis; D016014:Linear Models; D015225:Magnetoencephalography; D008959:Models, Neurological; D012016:Reference Values; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D014793:Visual Cortex / Q000502:physiology*