what is wrong?

[Maite Crespo]

Hello!

I read some previous mails in the discussion list, but I'm still not sure about 
the procedure I'm following. I'm obtaining too flat images (not spatially located 
sources). I would like to localize the source activity within a frequency band 
and a time window. I computed the CSD matrix using ft_freqanalysis. Can I 
average the resulting matrix in frequency and time before using it with 
ft_sourceanalysis? 

I used the following steps to compute the filters in the averaged CSD (across 
trials) and then apply it to compute the power in single trial data. Is that 
right? 

% 1st run
cfg=[];
cfg.frequency=5;
cfg.latency=.7;
cfg.method='dics';
cfg.projectnoise='yes';
cfg.keepfilter='yes';
cfg.grid=grid;
cfg.vol=vol;
cfg.elecfile=elecfile;
cfg.lambda=.05;
source=ft_sourceanalysis(cfg,data);

% 2nd run
cfg=[];
cfg.frequency=5;
cfg.latency=.7;
cfg.method='dics';
cfg.projectnoise='yes';
cfg.rawtrial='yes';
source.leadfield=grid.leadfield;
cfg.grid=source2grid(source);
cfg.vol=vol;
cfg.elecfile=elecfile;
cfg.lambda=.05;
source=ft_sourceanalysis(cfg,data);

I also tried changing the lambda parameter, but it seems there are not many 
changes...

Many thanks in advance for any help.

Best regards,
Maité

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