[FieldTrip] fixed dipole orientation for MNE

[Yuval Harpaz]

Well, it uses fixed orientation but it calculates the orientation based on
the signal, not on the anatomy. I am trying to reduce leakage problems by
limiting orientation according to structure. you CAN specify dip.mom but
this is really buggy.
thanks


On 18 June 2013 16:16, Eelke Spaak <eelke.spaak at donders.ru.nl> wrote:

> Dear Yuval,
>
> The LCMV and DICS beamforming implementations in FieldTrip support
> cfg.<method>.fixedori = 'yes', where <method> is either 'lcmv' or
> 'dics'. This will compute a filter which constrains each dipole to
> point in the strongest orientation. For SAM I think this is not
> implemented, and for MNE I have no clue.
>
> Does this answer your question? Or are you lookling for another type
> of fixed orientation, maybe based on anatomy or so?
>
> Best,
> Eelke
>
> On 18 June 2013 14:58, Yuval Harpaz <yuvharpaz at gmail.com> wrote:
> > Dear group
> > I would like to ask again
> > (
> http://mailman.science.ru.nl/pipermail/fieldtrip/2011-February/003456.html
> )
> > about head model with fixed dipole orientation (obtained from
> freesurfer),
> > as I saw no reply to the previous message.
> >
> > I understand that there is no civilized way, currently, to tell MNE or
> > beamforming to use fixed orientation, or am I wrong?
> >
> > applying 'sam' I managed to set dipole orinetation by making a dip.mom
> field
> > in addition to dip.pos and by
> > gain = lf;
> > instead of the existing
> > gain = lf * UnitMDip';
> > note that here lf is a vector (no 3 columns).
> >
> > However this is patchy and not thorough. So can you please tell me if
> there
> > is a way to do it with regular ft functions?
> > thank you
> > Yuval
> >
> >
> >
> >
> > Dr .Harpaz
> >
> > BIU MEG lab
> >
> > _______________________________________________
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> > fieldtrip at donders.ru.nl
> > http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
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-- 
Yuval




Dr .Harpaz

BIU MEG lab <http://faculty.biu.ac.il/~goldsa/index.html>
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