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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I have a dataset from an experiment where 12 participants were exposed to 3 levels of nitrous oxide, while I measured their EEG. I also have a baseline recording. I took for each exposure (and
baseline) a 1 minute sample for further analysis. I want to do source localization to better understand which parts of the brain are involved. I don’t have MRI scans of my participants, so I used the standard MRI and BEM. I would like to thanks the persons
who made the various manuals and analysis examples on the website, as they helped me tremendously to do this analysis.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">After cleaning and preprocessing, I combined the datasets into one for further analysis. I also chose to make 5 sec “trials” for further analysis. For this source analysis I loaded the data of
1 exposure and the baseline data, to compare them.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="p1"> %Calculate the channel covariance matric<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg = [];<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.covariance =
<span class="s1">'yes'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.covariancewindow =
<span class="s1">'all'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.keeptrials<span class="apple-converted-space">
</span>= <span class="s1">'yes'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>timelock = ft_timelockanalysis(cfg, data_filt);<o:p></o:p></p>
<p class="p3"><span class="apple-converted-space"> </span><o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>%Global filter<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg = [];<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.headmodel = vol;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.elec = elec_aligned;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.grid = grid;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.method = <span class="s1">
'lcmv'</span>;<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.lcmv.projectnoise=</span><span class="s1">'yes'</span><span class="s2">;
</span>%needed for neural activity index<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.lcmv.fixedori =
</span><span class="s1">'yes'</span><span class="s2">;</span><span class="apple-converted-space">
</span>%Project onto largest variance orientation<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.lcmv.keepfilter =
<span class="s1">'yes'</span>; <span class="s3">%Keep the beamformer weights</span><o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.lcmv.lambda =
<span class="s1">'5%'</span>; <span class="s3">%Regularise a little</span><o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.rawtrial</span><span class="apple-converted-space">
</span><span class="s2">= </span><span class="s1">'yes'</span><span class="s2">;</span><span class="apple-converted-space">
</span>% project each single trial through the filter.<span class="apple-converted-space"> </span><o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.keeptrials<span class="apple-converted-space">
</span>= <span class="s1">'yes'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>source = ft_sourceanalysis(cfg, timelock);<o:p></o:p></p>
<p class="p3"><span class="apple-converted-space"> </span><o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg = [];<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.dim <span class="apple-converted-space">
</span>= source.dim;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.method<span class="apple-converted-space">
</span>= <span class="s1">'montecarlo'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.statistic <span class="apple-converted-space">
</span>= <span class="s1">'ft_statfun_indepsamplesT'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.parameter <span class="apple-converted-space">
</span>= <span class="s1">'pow'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.correctm<span class="apple-converted-space">
</span>= <span class="s1">'cluster'</span>;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.numrandomization = 1000;<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.alpha
</span><span class="apple-converted-space"> </span><span class="s2">= 0.05; </span>
% note that this only implies single-sided testing<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.tail<span class="apple-converted-space">
</span>= 0;<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.design(1,:) = [1:nTrials 1:nTrials];<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>cfg.design(2,:) = [ones(1,nTrials) ones(1,nTrials).*2];<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.uvar</span><span class="apple-converted-space">
</span><span class="s2">= 1; </span>% row of design matrix that contains unit variable (in this case: trials)<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s2">cfg.ivar</span><span class="apple-converted-space">
</span><span class="s2">= 2; </span>% row of design matrix that contains independent variable (the conditions)<span class="apple-converted-space"> </span><o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span>stat = ft_sourcestatistics(cfg, source);<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">After the source analysis the source statistics script calls the checkdata script and I get the following error:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Index exceeds array bounds.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Error in ft_datatype_source (line 183)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> val{indx(k)}(1,:,:,:) = dat{indx(k)};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Error in ft_checkdata (line 278)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> data = ft_datatype_source(data);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Error in ft_sourcestatistics (line 94)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> varargin{i} = ft_checkdata(varargin{i}, 'datatype', 'source', 'feedback', 'no');<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Error in sourcelocalisation_N2O (line 114)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> stat = ft_sourcestatistics(cfg, source);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">The source struct has the following content:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> time: [1×15360 double]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> dim: [24 31 25]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> inside: [18600×1 logical]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> pos: [18600×3 double]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> method: 'rawtrial'<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> trial: [1×24 struct]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> df: 24<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> cfg: [1×1 struct]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">With source.trial:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> 1×24 struct array with fields:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> ori<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> pow<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> mom<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> noise<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> filter<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> label<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"> filterdimord<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">I would like your help to understand the error and how to fix it.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt">Xavier Vrijdag<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt"><o:p> </o:p></span></p>
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