[Eeglablist] dipole fit position outside head map

[Makoto Miyakoshi]

Dear Valentina,

Sorry for the late reply. I hope my response still helps!

> To plot each dipole I use the posxyz variable obtained from dipfit.model
structure.

This means you are using MNI coordinates. It should be fine.

If MNI-Tal confusion is not an issue, the next thing I can think of is the
coregistration failure. In order to evaluate it, however, you should show
me how much deviation your dipoles show from the template head. Can you
upload a screenshot to some server and paste a link so that I can access
it? Can you also check that your frontal dipoles are shown in the frontal
regions instead of the locations near the left ear? Such 90 degrees
rotation to the left can often happen.

Makoto


On Wed, Jul 27, 2022 at 9:18 AM Barone, Valentina (UT-TNW) via eeglablist <
eeglablist at sccn.ucsd.edu> wrote:

> Dear eeglab team,
>
> I am defining single equivalent dipole localization using the
> dipfit_erpeeg() function with eeglab during a generalized seizure. I do
> that in a loop for each sample (sampling freq is 256 Hz) of the seizure,
> and then I plot all the dipoles on the MNI BME head model I use to define
> the dipoles. Once I plot the position of my dipoles in the same 3-d volume
> map used to define the dipoles, a couple of dipoles are positioned outside
> the head map. To plot each dipole I use the posxyz variable obtained from
> dipfit.model structure.
> I do not understand how can some dipoles be positioned outside the head
> model used to fit the dipoles. Is anybody familiar with these results and
> can explain why this happens?
>
> Thanks a lot in advance for your help.
>
> Best regards,
>
> Valentina
> _______________________________________________
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to
> eeglablist-unsubscribe at sccn.ucsd.edu
> For digest mode, send an email with the subject "set digest mime" to
> eeglablist-request at sccn.ucsd.edu
>