EEG dipole source localization

Considers using inverse solutions for determining source locations. Dipole source localization using EEGs recorded from the scalp is widely used to make estimates of the locations of sources of electrical activity in the brain. Such information can be very useful for both clinical and research applications. For example, in clinical applications, accurate information about the location of an epileptic focus (source) in the brain can be used to plan surgery for its removal. Likewise, information about the regions of the brain that process various signals (e.g., an auditory tone) can provide valuable research information about the functioning of the brain. It is necessary to assume a model of the source and a model of the head in order to estimate the location of a source. Once these models are selected, an inverse solution can be calculated for the location of the source in the head model. This source is then assumed to represent the actual source. The accuracy with which a source can be located by this method is affected by a number of factors including source-modeling errors, head-modeling errors, measurement-location errors, and EEG noise. This article presents a review of the research dealing with the effects of these factors on localization accuracy.