title: Effects of head models and dipole source parameters on EEG fields.
abstract: Head model and an efficient method for computing the forward EEG (electroencephalography)problem are essential to dipole source localization(DSL). In this paper, we use less expensive ovoid geometry to approximate human head, aiming at investigating the effects of head shape and dipole source parameters on EEG fields. The application of point least squares (PLS) based on meshless method was introduced for solving EEG forward problem and numerical simulation is implemented in three kinds of ovoid head models. We present the performances of the surface potential in the face of varying dipole source parameters in detail. The results show that the potential patterns are similar for different dipole position in different head shapes, but the peak value of potential is significantly influenced by the head shape. Dipole position induces a great effect on the peak value of potential and shift of peak potential. The degree of variation between sphere head model and non-sphere head models is seen at the same time. We also show that PLS method with the trigonometric basis is superior to the constant basis, linear basis, and quadratic basis functions in accuracy and efficiency.
authors.affiliation: Mathematics and Science College, Shanghai Normal University, 100 Guilin Road, Shanghai 200234, P.R.China.
authors.forename: Li
authors.initials: L
authors.lastname: Peng
authors.affiliation: College of Informatics, South China Agricultural University, Guangzhou 510642, P.R.China.
authors.forename: Mingming
authors.initials: M
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Functional Material for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road 200050, Shanghai, P.R. China.
authors.forename: Anhuai
authors.initials: A
authors.lastname: Xu
keywords: Electroencephalography(EEG) and dipole source; localization potential head model integral equation.