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Dear Vladimir,


Great, many thanks again!


Best wishes,
Ulrich


From: Vladimir Litvak <[log in to unmask]>
Sent: 25 February 2019 13:13
To: Pomper, Ulrich
Cc: [log in to unmask]
Subject: Re: [SPM] PLV / ITC source estimation
 
Dear Ulrich,

Yes, I think this is a good way to do it.

Vladimir

On Mon, Feb 25, 2019 at 1:12 PM Pomper, Ulrich <[log in to unmask]> wrote:

Dear Vladimir,


Many thanks for your help!

May I ask: As a reviewer, would you agree with the following procedure:


  1. Data at scalp-level show ITC effect at certain time-frequency window.
  2. For source estimation of this effect, the evoked response at this time-frequency window is inverted.
  3. Optionally, just as a double check, the time-series at the voxel with the maximum source activity is extracted, and ITC is demonstrated again for these data.

Best wishes,
Ulrich





From: Vladimir Litvak <[log in to unmask]>
Sent: 25 February 2019 11:53
To: Pomper, Ulrich
Cc: [log in to unmask]
Subject: Re: [SPM] PLV / ITC source estimation
 
Dear Ulrich,

In principle, inter-trial coherence has a very close relation to ERP so it's unlikely that the sources of the two are different. The way you would localise an ITC effect is by doing source reconstruction of your epoched data, followed by source extraction, then computing ITC at the source level and then doing stats on that. If you are interested in specific ROIs, that's quite easy. If you want to do it for the whole mesh, it can also be done but with slightly more tweaking. 

Best,

Vladimir

On Fri, Feb 22, 2019 at 9:08 AM Pomper, Ulrich <[log in to unmask]> wrote:

Dear SPM users,


My apologies for bumping my question, I just thought I'd give it a second try.

If anyone has an idea on how to compute source estimates of Intertrial-coherence I'd very much appreciate your help!


Best wishes,

Ulrich





From: Pomper, Ulrich
Sent: 13 February 2019 11:11
To: [log in to unmask]
Subject: PLV / ITC source estimation
 

Dear SPM users,

 

In my data, have found a significant difference in inter-trial coherence / phase locking between two conditions at the scalp level. Now I would like to calculate a source estimate of that ITC effect, similar to a source inversion of a power effect in a certain time-frequency window. Could anybody point me in a direction how to do that?

I know how to invert time-frequency data and evoked fields, but I haven’t seen anything on ITC yet.

I’d be very grateful for any help in that regard!

 

Many thanks,

Ulrich




--
Dr. Ulrich Pomper
 
Department of Basic Psychological Research and Research Methods
University of Vienna
Austria