[FieldTrip] phase difference between sources

Jan.Hirschmann at med.uni-duesseldorf.de Jan.Hirschmann at med.uni-duesseldorf.de
Thu Sep 6 15:06:02 CEST 2012


Dear fieldtrip experts,

 

I was wondering how to get the mean phase difference between two sources A and B at a particular frequency f (mean across data segments). My idea was to use dics and to say cfg.refdip=A and cfg.keepcsd='yes'. Then I would get C, the cross spectral density between A and B, which is a 3x3 matrix with complex entries. Joachim Gross wrote that one could estimate csd in the dominant direction as the trace of C. So I guess I could get the phase difference by angle(trace(C)). Is this correct? If I wanted to use SVD to estimate the dominant direction instead of the trace, how would I get the phase difference then? And finally, if I wanted to have coherence not with the dipole orientation that maximizes power but with the orientation that maximizes phase difference, how would that work?

 

Thanks for any remarks!

Jan

 

--

Jan Hirschmann

MSc Neuroscience

Institute of Clinical Neuroscience and Medical Psychology

Heinrich Heine University Düsseldorf

Universitätsstr. 1

40225 Düsseldorf

Germany

Tel: +49 (0)211 81 18415

Fax: +49 (0)211 81 19033

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20120906/f8615f55/attachment.html>


More information about the fieldtrip mailing list