LORETA to fieldtrip

Vladimir Litvak litvak at TECHUNIX.TECHNION.AC.IL
Wed Mar 29 18:36:23 CEST 2006

Hi again,

I made some progress with loreta2fieldtrip function. It supports both the
new sLORETA and the old LORETA format. I had to prepare two resampled MRI
scans of Collin to match to each kind of LORETA file. I attach the function,
these scans, the index file that is necessary for the conversion and two
example files for LORETA and for sLORETA. To test the function you should

volume=loreta2fieldtrip('test.slor', 1);
volume=loreta2fieldtrip('test.lorb', 1);

Now I would like you to help me finalize this function to produce something
suitable for statitistical analysis. As I said yesterday with the sizes I
actually got it shouldn't be a problem to run time-space test. It's probably
not necessary to include the anatomy in every volume so the final function
should have this as an option. Also I'm not sure whether avg.pow is the
right place to put the functional data in this case. Another issue is
coordinate system. What I understood from Roberto is that his MNI
coordinates correspond to voxels in the original not downsampled Collin scan
(such as the one I sent you before). The origin is [91 127 73].

The lCollin was obtained by downsampling the original Collin with (4:7:end,
4:7:end, 4:7:end) and the slCollin with (1:5:end, 2:5:end, 3:5:end). So if
it is necessary to store the MNI coordinates or transformation matrix in the
volume, please figure out how this should be done. 

Then I would appreciate an example of how to run for instance a dependent
sample t-test on this data with your new statistics functions.

What I really need to do is dependent samples regression with 4 conditions
and up to 10 subjects. If this is possible with your present functions
please send me an example as well. I hope that if I have these examples I'll
be able to keep further developing them as I've been doing until now.

If you want, you can include this loreta2fieldtrip extension in Fieldtrip
after we finish polishing and testing it.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: loreta2fieldtrip.zip
Type: application/x-zip-compressed
Size: 106645 bytes
Desc: not available
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20060329/ddeab89b/attachment-0002.bin>

More information about the fieldtrip mailing list