single trial source signal

[Hanneke Van Dijk]

Dear Vasan,

I also feel single-trial source-analysis does work, I have done it and published it J Neurosci (using pcc for just power data).

The problem as you sent it in the mail below is that the cfg.grid.pos that you entered is not inside your headmodel:
0 dipoles inside, 1 dipoles outside brain

There wil not be any data in there. You could try to plot the functional data interpolated on the mri with cfg.interactive = 'yes'; and then click on the location you want to do the single-trial analysis on. The coordinates will be printed in the workspace. These can be entered in cfg.grid.pos.

If you have any more questions could you then send the cfg you used as well? This might give some hints as to what went wrong.

It's just not the case that you can use some-one elses code and run your data through it. The choises you make for the data analysis depend a lot on the kind of data and what you want to do.
But this mailing list is there to help you allong the way!

Hope it helps,

Best, Hanneke




-----Oorspronkelijk bericht-----
Van: van Dijk, Hanneke
Verzonden: zo 29.11.2009 09:38
Aan: FieldTrip discussion list
Onderwerp: RE: [FIELDTRIP] single trial source signal
 
Dear Vasan,

Since I don't know exactly how far you are in doing the analysis, I just send you the basic script that shows the most important parameters. Don't forget to do freqanalysis with cfg.output = 'fourier' and cfg.method = 'mtmfft' for the specific frequency (cfg.foilim) you want to focus on.

cfg                 = [];
cfg.grid.pos        = location of source coordinate;% [x y z] to fill in
cfg.frequency       = frequency of interest;
cfg.vol             = headmodel; %to make yourself see http://fieldtrip.fcdonders.nl/example/make_leadfields_using_different_headmodels
cfg.projectnoise    = 'yes';%to compute the neural activity index using sourcedescriptives
cfg.lambda          = '10%';%the amount of noice to estimate estimated
cfg.method          = 'pcc';
cfg.keeptrials      = 'yes';
Virtual_channeldata = sourceanalysis(cfg,freq);

You can do sourcedescriptives after that.

'help freqanalysis', 'help sourceanalysis' and 'help sourcedescriptives' should also help you further. Or you could have a look at the fieldtrip website. There are a lot of options to taylor the analysis to your data.

Hope this helps!

Best,

Hanneke van Dijk

------------------------------------------------------------
Institute for Clinical Neuroscience and Medical Psychology
Heinrich Heine Universitaet, Duesseldorf, Germany
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-----Oorspronkelijk bericht-----
Van: FieldTrip discussion list namens Rajamoni Nadar, Sreenivasan (NIH/NIMH) [E]
Verzonden: do 26.11.2009 14:53
Aan: FIELDTRIP at NIC.SURFNET.NL
Onderwerp: [FIELDTRIP] single trial source signal
 
FieldTrip Users,

Is it possible to get single trial source signal using FieldTrip? I would appreciate if anybody could provide code for the same.

Thank you,
Vasan
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The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/neuroimaging/fieldtrip.



----------------------------------
The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/neuroimaging/fieldtrip.
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