[FieldTrip] using sloreta in FieldTrip

Ingrid Lyda Catharina Nieuwenhuis inieuwenhuis at berkeley.edu
Wed Apr 24 07:39:20 CEST 2013


Hi all,

Does anyone has experience with using FieldTrip for looking at sources
generated using the Loreta-key program? I've generated sLoreta files and
read them into FieldTrip using loreta2fieldtrip as described on the
FieldTrip wiki<http://fieldtrip.fcdonders.nl/integrating_with_loreta?s[]=loreta>
.
Note, I first got an "Invalid precision" error from fread due to line 89:
activity = fread(fid, [voxnumber 1], 'float = >single'); But after I
changed this line to: activity = fread(fid, [voxnumber 1]); it worked.

But now I'd like to plot this on an anatomical MRI since without anatomy it
looks hard to interpret (see attached). The source should be in MNI space
(see info on loreta-key
page<http://www.uzh.ch/keyinst/NewLORETA/sLORETA/08Slor.html>),
so I tried using the T1.nii template from SPM (that's in MNI space,
correct?:

%read in template MRI (MNI)
    template =
ft_read_mri('C:\Users\Ingrid\Documents\MATLAB\FieldTrip\external\spm8\templates\T1.nii');
    template.coordsys = 'spm'; % so that FieldTrip knows how to interpret
the coordinate system

    % interpolate
    cfg = [];
    cfg.parameter = 'avg.pow';
    [interp] = ft_sourceinterpolate(cfg, GA_source, template);

    %sourceplot
    cfg = [];
    cfg.method = 'ortho';
    cfg.funparameter = 'avg.pow';
    cfg.coordsys      = 'mni';
    ft_sourceplot(cfg,interp);

But that doesn't work (see capture2). I'm a bit lost now... Anyone any
ideas? Maybe I should use the "mni152" template. since that is what the
loreta website says it's based on. Anyone know where to get that template
in a format FieldTrip can read?

So in short:
1) has anyone done this before and has tips / code to share?
2) is the T1.nii template from SPM in MNI space?
3) do you think the mni152 is different from T1.nii, and would work? if so
anyone know where to get it in format FieldTrip can read?
4) am I missing something in steps explaining why my source does not match
the anatomy?

Thanks!
Ingrid

-- 
Ingrid Nieuwenhuis PhD
Postdoctoral Fellow
Sleep and Neuroimaging Laboratory
Department of Psychology
University of California, Berkeley
California 94720-1650
Tolman Hall, room 5305
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20130423/3a15e623/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Capture.PNG
Type: image/png
Size: 48260 bytes
Desc: not available
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20130423/3a15e623/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Capture2.PNG
Type: image/png
Size: 94462 bytes
Desc: not available
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20130423/3a15e623/attachment-0003.png>


More information about the fieldtrip mailing list