[Mne_analysis] head position information when building forward model for different runs

Alexandre Gramfort alexandre.gramfort at inria.fr
Thu Mar 21 16:11:44 EDT 2019
Search archives:

        External Email - Use Caution        

hi Lin,

did you average dSPM values? as given the noise normalization the average
of the dSPM is not the dSPM of the average. If could make a big difference
unless all runs have the same number of epochs in all conditions.


On Thu, Mar 21, 2019 at 6:07 PM Lin Wang <wanglinsisi at gmail.com> wrote:

>         External Email - Use Caution
> Hi MNE experts,
> I have a question about what head position information to use when
> building a forward model for each run in one participant.
> We have eight runs of MEG data. At the beginning, we used the head
> position of the first run to build just one forward model for one
> participant. Then we thought it might be more accurate to use the
> run-specific head position to build forward models separately for different
> runs. In both analyses, the forward models were used to calculate the
> inverse operators, which were applied to the evoked response for each run.
> We then averaged the activation across runs within each participant.
> Finally, we compared the activation difference between two conditions at
> the group level.
> Although the group-averaged activation looks very similar from the two
> analyses, the use of run-specific head position reduced the statistical
> power at the group level. Do you know why?
> Is there a better way to account for the head movement within each run? We
> didn't apply the MaxFilter to the data because the head movement was not
> considered to be serious during the data acquisition. Is there a way to
> incorporate the head movement within each run or the whole experiment
> without running the MaxFilter?
> Thanks a lot for your input!
> Best,
> Lin
> _______________________________________________
> Mne_analysis mailing list
> Mne_analysis at nmr.mgh.harvard.edu
> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/mne_analysis
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.nmr.mgh.harvard.edu/pipermail/mne_analysis/attachments/20190321/6d85588a/attachment.html 

More information about the Mne_analysis mailing list