mne and ft_sourceinterpolate

[Gregor Volberg]

Dear fieldtrippers,

I am trying to extract source activity from timelock-data, and I would like to have this for a whole epoch of 1 sec / 501 sample points. I did an ft_sourceanalysis with method = 'mne', which worked fine and gave the desired source activity (see structure "source" below; field "avg" contains "mom" and "pow"). Next I did an ft_sourceinterpolate with "source" and a standard mri as input. Unfortunately, the resulting structure did not contain an "avg" field any more (see "ivol" below) - my functional data got lost during interpolation. Did someone have a similar problem or does someone know a solution?

Many thanks in advance for any help!
Gregor

P.S.: Source interpolation works without problems with method = 'lcmv', but this gives the mean source activity within the desired time range rather than sample-wise activity. It is not a good idea to apply the lcmv beamformer to consecutive time bins and then concatenate the source activity, am I right?



source = 

      xgrid: [-66 -56 -46 -36 -26 -16 -6 4 14 24 34 44 54 64]
      ygrid: [-105 -95 -85 -75 -65 -55 -45 -35 -25 -15 -5 5 15 25 35 45 55 65]
      zgrid: [-46 -36 -26 -16 -6 4 14 24 34 44 54 64 74 84]
        dim: [14 18 14]
        vol: [1x1 struct]
       time: [1x501 double]
        pos: [3528x3 double]
     inside: [1x1808 double]
    outside: [1x1720 double]
     method: 'average'
        avg: [1x1 struct]
        cfg: [1x1 struct]

ivol = 

       inside: [181x217x181 logical]
          dim: [181 217 181]
    transform: [4x4 double]
      anatomy: [181x217x181 uint8]
          cfg: [1x1 struct]



-- 
Dr. rer. nat. Gregor Volberg <gregor.volberg at psychologie.uni-regensburg.de> ( mailto:gregor.volberg at psychologie.uni-regensburg.de )
University of Regensburg
Institute for Experimental Psychology
93040 Regensburg, Germany
Tel: +49 941 943 3862 
Fax: +49 941 943 3233
http://www.psychologie.uni-regensburg.de/Greenlee/team/volberg/volberg.html
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