[FieldTrip] Granger Causality Analysis after Beamformer

[Helen Wieffering]

Dear FieldTrip users,

I am writing to ask for any available guidance on computing granger
causality measures using ft_connectivity_analysis in FieldTrip.

Our data comes from 128 EEG channels. So far we have:
- cleaned and preprocessed the data
- computed frequency analysis using 'mtmfft' at 6 Hz
- localized sources of 6hz activity to a normalized head model using
Beamformer and method 'dics'.

We would now like to compute connectivity analysis between the strongest
sources, using granger causality. I have read through the FieldTrip
tutorials, but am still not sure how to proceed.

Mainly, my question is whether we should have first computed
ft_mvaranalysis with our preprocessed data, and then done frequency
analysis using cfg.method = 'mvar' and proceeded with source analysis
(Beamformer) from there. Should we go back and complete those steps? I'm
also wondering about the best method for selecting sources to use for
connectivity analysis.

If anyone has had success with this, I'd love to hear!

Thanks in advance.

Helen Wieffering
Erika Nyhus
Dept. of Neuroscience
Bowdoin College
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20150730/55e13014/attachment-0001.html>