Extraction of source time series and computing coherence are two
different issues. There are tools in SPM for extracting source time
series as Johannes mentioned there should be no problem to compute
coherence on extracted sources (except for volume conduction issues).
There are some tools in MEEGTools toolbox for computing steady state
coherence ('Vector-AR connectivity measures') and event-related
coherence ('Fieldtrip-SPM robust multitaper coherence') but more
flexible tools are available in Fieldtrip (which is also included in
SPM), see http://fieldtrip.fcdonders.nl/tutorial/coherence
Best,
Vladimir
On Fri, Nov 25, 2011 at 9:05 AM, Johannes Gehrig <[log in to unmask]> wrote:
> Dear JHL,
>
> I don't now if it is possible to do it completely with spm. My approach was first to do spm groupinversion afterwards a source extraction (of single trial time-courses), export the data to fieldtrip and calculated the coherence unfortunately in my case this didn't work, because the sources are too close to each other and I had some volume conduction. The other option could be to extract the sources with the beamformer but then I'm not sure if the phase information remains.
>
> Hopefully this helps!
>
> Best,
> Johannes
>
> -----Ursprüngliche Nachricht-----
> Von: "Jung L Hsu" <[log in to unmask]>
> Gesendet: 25.11.2011 05:40:46
> An: [log in to unmask]
> Betreff: [SPM] calculate coherence in spm8
>
>>Dear SPM experts,
>>I would like to calculate region to region coherence (base on the AAL region) in continuous EEG data. is it possible to use spm8 to do it ? or any suggestion ?
>>best
>>JLH
>
>
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