Code EEG

EGI Hydrocel sLORETA coordinates and Transform Files

Past few months have been crazy with postdoc interviewing and paper writing. Just thought I’d take a few minutes out to share some useful files for folks interested in analyzing EEG data from the 256 channel EGI Hydrocel System in sLORETA. Can be a pain figuring out how transform the EGI coordinates to the standardized MNI space in order to estiamte the sLORETA transformation matrix, so this’ll might save you some time if you’re trying to do that. These files assume Cz has been retained but just go ahead and delete the last line of the .sxyz file in your favorite text editor and use that file to recompute the sLORETA transform if you’ve dumped Cz from your files. Happy Analyzing! Coordinate file : Hydrocel_257_coordinates.sxyz sLORETA spinv transformation coordinates : Hydrocel_257_coordinates

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EEG Research Thoughts

Temporal-Spatial Decomposition in ERP Analysis : A General Introduction

Most of my work focuses on EEG related measures. While I do conduct some single-trial, time-frequency, electrotomographic and connectivity based analyses, it’s hard to disregard the rich body of work involving classic ERP components. I suppose the analogue to “Ahh, but does it run Crysis” in the EEG world might be “Ahh, but does it P300”? (the overlap in the Venn diagrams of folks who get those jokes is might be fairly small, but I think it’s funny so it stays!). Focusing on the simple case of finding a P300, say to an auditory oddball paradigm. Imagine you went all out on equipment and collected some awesome 256 electrode high density datasets. What next? How do you decide When and Where that P300 component arises? No problem! I’ll just look at the literature and use what other folks use. A few hours later, you’re surrounded by papers proclaiming the P300 is …

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