[FieldTrip] Urgent: Error in Source Statistics, Group level

[Eelke Spaak]

Dear Chaitanya,

Perhaps an obvious question: do you find any significant differences in the
statistics step (inspect the stat structure)? If not, the mask will consist
of all zeroes, hence giving you a 'blank' plot.

Best,
Eelke


On 26 January 2014 08:46, Chaitanya Srinivas <chaitanya.pro at gmail.com>wrote:

> Dear fieldtrip users,
> I would like to do sourcestatistics on a group level with eeg data. I have a
> pre and post intervention measurement for each of my 10 subjects
> . After source reconstruction using an DICS beamformer
> and volume normalization, I calculated the sourcegrandaverage for the pre and
> post condition and i have avg.pow for each subject.
>
>  However, when I use the grandaverage results in ft_sourcestatistics in the
> configuration shown below and plot the result I just get a blank anatomical
> mri. It only runs with cfg.parameter="pow" .I tried with cfg.parameter = 'avg.pow' it doesnt run.
> Do I have to set any additional parameters or am I making some mistake?
>
>
> cfg=[];
> cfg.dim         = grandAVGsourcePre.dim;
> cfg.method      = 'montecarlo';
> cfg.statistic   = 'depsamplesT';
> cfg.parameter   = 'pow';
> cfg.correctm    = 'cluster';
> cfg.numrandomization = 1000;
> cfg.alpha       = 0.05;
> cfg.tail        = 0;
>
> nsubj=length(sourcePre.trial);
> cfg.design(1,:) = [1:nsubj 1:nsubj];
> cfg.design(2,:) = [ones(1,nsubj) ones(1,nsubj)*2];
> cfg.uvar        = 1;
> cfg.ivar        = 2;
> stat = ft_sourcestatistics(cfg, grandAVGsourcePre, grandAVGsourcePost);
>
>
> *and next interpolation*
>  cfg                                       = [];
>
>  cfg.voxelcoord                      = 'no';
>  cfg.parameter                       = 'mask';
>  cfg.interpmethod                   = 'nearest';
>  cfg.coordsys                        = 'mni';
>
>  mask                                  = ft_sourceinterpolate(cfg,stat,mri);
>  statplot.mask                      = mask.mask;
>
>
> *and then for plotting*
>
> cfg = [];
> cfg.method        = 'slice';
> cfg.funparameter  = 'stat';
> cfg.maskparameter = 'mask';
>    cfg.funcolorlim   = [-0.1 0.1];
>    cfg.opacitylim    = [-0.1 0.1];
> figure
> ft_sourceplot(cfg, statplot);
>
>
>
>
>
>
>
>
>
> * ===============================================*
>
>
> *[image: Inline image 1]*
> *Best Regards*
>
>
> *Chaitanya Srinivas Lanka Wiss. Mitarbeiter
>                                       *
>
> *PhD Student Functional and Restorative Neurosurgery Neural Information
> ProcessingNeurosurgical University Hospital*
>
> *             Graduate Training Center for Neuroscience  Eberhard Karls
> University                          Eberhard Karls University **Otfried-Mueller-Str.45
> Österbergstr. 3*
> *  D-72076 Tuebingen                                    **D-72074
> Tuebingen*
>
> *Mobile Phone Number : +49-176-79035731*
> *===============================================*
>
> _______________________________________________
> fieldtrip mailing list
> fieldtrip at donders.ru.nl
> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20140126/29290488/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 23195 bytes
Desc: not available
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20140126/29290488/attachment-0002.png>