Question: How to extract GFP/amplitude of ROI timeseries

[jnvandermeer]

Hello,

Is there a way (or what is the best way, using your toolbox) to estimate a timeseries of source 'global field power', given a parcellation (within the ROIs), i.e. a measure of neural activation, in absolute value(s) rather than in positive-negative values.

In this case, I am not so much interested in connectivity per-se; just a way to be able to view an ERP of activation, for each ROI.

Many thanks
Johan