[Eeglablist] high density EEG, source localization and electrode positions

[Sara Graziadio]

Hello everybody,
We are setting up an ERP study with high density EEG (128 electrodes). We would like to localize sources from the ERP components and possibly to relate these data with fMRI activations. We would have MRI data of the subjects. We are now in the process of considering the possibility to use the Polhemus to digitalize the electrode positions and we found out that there are no papers (at least that I can find) that compare the accuracy of source localization with high density EEG adding the information about the positions of all the 128 electrodes, or of just a part of them (for example 30 evenly spread on the scalp and including some of the more external positions), or just using the standard 10-10 system locations. Does anybody of you have any thoughts about it? Have you had ever tried to compare the 3 options I have described? 
Thank you very much

Best wishes

Sara Graziadio, PhD
Research Associate
Newcastle University