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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Dear List,<br>
<br>
I adressed a similar issue before (http://mailman.science.ru.nl/pipermail/fieldtrip/2015-May/009237.html), which I would like to extend with some more information and the used code. I am interested in computing a permutation test for coherence between two conditions
based on cluster statistics. The conditions are rest and activation. However I do not manage to get the source statistics to work, as it gives me an error stating:<br>
<br>
Error using ft_selectdata>getselection_pos (line 1123)<br>
not yet implemented<br>
<br>
Error in ft_selectdata (line 263)<br>
if haspos, [selpos, cfg] = getselection_pos (cfg, varargin{:}, cfg.tolerance, cfg.select); end<br>
<br>
Error in ft_sourcestatistics (line 119)<br>
[varargin{:}] = ft_selectdata(tmpcfg, varargin{:});<br>
<br>
I assume my design for the stats is not correct, but I'm not sure what this error is actually telling me and I would appreciate any help.<br>
Thanks in advance.<br>
<br>
%% computing cross-spectral density matrices<br>
cfg = [];<br>
cfg.method = 'mtmfft';<br>
cfg.output = 'fourier';<br>
cfg.taper = 'dpss';<br>
cfg.tapsmofrq = 0.5*(abs(diff([3 8])));<br>
cfg.frequency = 5.5;<br>
cfg.keeptrials = 'yes';<br>
cfg.channel = {'EEG', 'EMG'};<br>
cfg.channelcmb = {'EEG' 'EEG'; 'EMG' 'EEG'};<br>
freqRest = ft_freqanalysis(cfg, data_rest);<br>
freqAct = ft_freqanalysis(cfg, data_act);<br>
<br>
%% computation of common filter <br>
dataAll = ft_appenddata([], data_rest, data_act);<br>
freqAll = ft_freqanalysis(cfg, dataAll);<br>
<br>
%% Leadfield matrix generation<br>
cfg = [];<br>
cfg.elec = sens; <br>
cfg.vol = vol; % vol from individual MRI (computed before)<br>
cfg.reducerank = 3;<br>
cfg.channel = {'EEG'};<br>
cfg.grid.resolution = 5; % use a 3-D grid with a 5 mm resolution<br>
cfg.grid.unit = 'mm';<br>
cfg.normalize = 'yes';<br>
[grid] = ft_prepare_leadfield(cfg);<br>
<br>
%% Source analysis with DICS beamformer<br>
cfg = [];<br>
cfg.frequency = 5.5;<br>
cfg.grid = grid;<br>
cfg.method = 'dics';<br>
cfg.refchan = 'EMG';<br>
cfg.channel = {'EEG' 'EMG'};<br>
cfg.tapsmofrq = 0.5*(abs(diff([3 8])));<br>
cfg.vol = vol;<br>
cfg.dics.projectnoise = 'yes';<br>
cfg.dics.lambda = '5%';<br>
cfg.dics.keepfilter = 'yes';<br>
cfg.dics.realfilter = 'no';<br>
sourceAll = ft_sourceanalysis(cfg, freqAll);<br>
cfg.grid.filter = sourceAll.avg.filter; % common flter as computed before<br>
<br>
sourceAct = ft_sourceanalysis(cfg, freqAct);<br>
sourceRest = ft_sourceanalysis(cfg, freqRest);<br>
sourceRest.time = data_rest.time;<br>
sourceAct.time = data_act.time;<br>
<br>
% At this point, data is concatenated into two structures, where each cell includes data of one subject for both rest (=baseline, sourceRest_all) and activation (sourceAct_all).<br>
<br>
%% Group statistics<br>
cfg = [];<br>
cfg.channel = 'all';<br>
cfg.avgovertime = 'yes';<br>
cfg.parameter = 'avg.coh';<br>
cfg.method = 'montecarlo';<br>
cfg.statistic = 'ft_statfun_depsamplesT';<br>
cfg.alpha = 0.05;<br>
cfg.correctm = 'cluster';<br>
cfg.numrandomization = 1000;<br>
<br>
nsubj=numel(sourceAct_all);<br>
cfg.design(1,1:2*nsubj) = [ones(1,nsubj) 2*ones(1,nsubj)];<br>
cfg.design(2,1:2*nsubj) = [1:nsubj 1:nsubj];<br>
cfg.ivar = 1; % the 1st row in cfg.design contains the independent variable<br>
cfg.uvar = 2; % the 2nd row in cfg.design contains the subject number<br>
<br>
stat = ft_sourcestatistics(cfg,sourceAct_all{:},sourceRest_all{:});<br>
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<font face="Tahoma" size="2"><font color="003366">Dr. David Pedrosa<br>
</font></font><font color="003366" face="Tahoma" size="2"><br>
Clinical Research Fellow</font><font color="003366" face="Tahoma" size="2"><br>
</font><font color="003366" face="Tahoma" size="2"><span dir="ltr" style="font-size:10pt">
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<div><span style="font-size:13px">
<div><font size="2"><span style="font-size:10pt">Medical Research Council Brain Network Dynamics Unit at the University of Oxford<br>
Nuffield Department of Clinical Neurosciences</span></font></div>
<div>University of Oxford</div>
<div>Level 6, West Wing</div>
<div>John Radcliffe Hospital, OX3 9DU<br>
</div>
</span></div>
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</span></font><font color="003366" face="Tahoma" size="2"><span style="font-size:10pt"><u>Tel:</u>
</span></font><font face="Tahoma" size="2"><span style="font-size:10pt"><font color="003366">+44 (0)1865 572490<br>
<u>E-Mail:</u> </font><font color="333333">david.pedrosa@ndcn.ox.ac.uk<br>
</font></span></font><font size="2"><span style="font-size:10pt"><br>
<a href="http://www.mrcbndu.ox.ac.uk/" target="_blank">http://www.mrcbndu.ox.ac.uk/</a></span></font><br>
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