Mapping the Event Related Potentials of the Brain: Theoretical Issues, Technical Considerations, and Computer Programs

摘要

Event-related potentials (ERPs) are the summed membrane potentials of large numbers of simultaneously active neurons. To determine the anatomical location of the population of cells that produces a specific ERP, one must first record its responses from a number of points to characterize the spatial distribution of its surface field. A number of factors affect the validity of spatial analyses of ERP phenomena. These include the number of recording electrodes used, the choice of the reference electrode, any distortions introduced when preprocessing the EEG, and any distortions introduced by the mapping process itself. This report discusses a variety of methods that have been used to generate spatial representations of the electroencephalogram. It deals with pertinent aspects of the recording process, as well as with the spatial analysis per se. Some limitations of the various approaches are described, and a general plan of implementation adaptable to most situations is outlined. The Appendix contains two computer programs that can be used to generate surface-distribution maps of ERPs. Keywords: Brain mapping, Evoked potentials, Electroencephalography. (aw)