Sorry to bother. I am an epileptologist who is venturing into a master’s research project. I have gone through all the necessary tutorials, but I still have some doubts.
I plan to use epochs (I could not find a protocol specifying the exact number) from EEG recordings with a 10–20 montage during relaxed wakefulness in patients with epilepsy, both before and after VNS. My goal is to evaluate the functional connectivity patterns and compare responders versus non-responders.
I was considering using approximately 5 to 6 epochs of 30 seconds each (though I am not sure if this is too few). Regarding the pipeline, I can follow it up to the source reconstruction stage without issues. My main question concerns which functional connectivity model would be most appropriate to use and how to perform the comparison of networks within the same patient across different time points.
Thanks, that way is even easier, because I can bypass any artifacts with short epochs. About the best way to compute the connectivity with low density EEG, any tips?
I recommend using power envelope connectivity (PEC) for functional connectivity analysis, as this method is said to be minimally affected by volume conduction effects of EEG source reconstruction. However, the functional connectivity methods can be mainly split into 2 categories: directions and variables. Directed method (like Granger Causality) will tell you which ROI is the information from and which ROI is it to. Multi-variable method (like partial mutual information (PMI)) will take all channels into consideration when calculating the correlation of 2 ROIs. You can choose whatever you want to get scientifically sound results.