Phase amplitude coupling mean and preferred phase angles

Dear all,

a)If I want to compare the PAC between two groups(treated/nontreated) should I use the MaxPAC value (it appears on the comodulogram) or the mean value?

b) How to get or where is listed the mean value of the PAC? (I calculated the PAC simultaneously for 4 channels).

c) Is it possible to get a polar plot/circular histogram for PAC which could be used to indicate the preferred phase angles for PAC?

Thank you!

@Samiee @Sylvain?

The PAC values are stored in the .mat output file generated by the process.
You can use either statistics (max or mean PAC) to run sample comparisons. I believe we still need to make sure these files can be processed by Brainstorm’s inferential statistics toolkit @MartinC?
The polar graphs for phase representation are a great idea they are not available yet in the app. Let’s put that on our list!

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Thank you all!

Hi Joska,

a) You can use either, I would suggest you find the best mode of coupling using comodulogram (e.g. theta to low gamma), and then run a single band tPAC analysis using the selected bands. In this step, you can compare average PAC values.

b) The mean value for PAC can be achieved using Frequency > Time-resolved Phase-Amplitude Coupling
(As Sylvain suggested, it would be awesome if all statistical tools in brainstorm works on PAC files as well)

c) Preferred phase of coupling is stored in the the output file (sPAC_avg.DynamicPhase), you can export it to matlab and analyse/see the preferred phase there. Polar plot is a good idea, but we cannot do it for all pixels of comodulogram plot, so we can plot it for the fp-fA pair with maximum coupling, or for single band mode.

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Thank you, Samiee!