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Hi Marco,<br>
<br>
> I have tested the Process > Sources > Fieldtrip:
ft_prepare_leadfield on<br>
> different MEG data (always recorded from an Elekta 306 sensors
system), and<br>
> I get an error "cannot work on balanced gradiometer definition"
<br>
<br>
For some reason, ft_plot_sens doesn't want to get passed both the
gradiometers and the magnetometers at once.<br>
Just run the process without the option "Display sensor/MRI
registration" and you won't get this error any more.<br>
<br>
<br>
> I also have a basic question on the data to put in the process:
my<br>
> understanding is that I should feed the process with the
segmented anatomy, <br>
> that I identify with (for the default anatomy) the
"Cortex_15002V" in the<br>
> anatomy tab. However, I cannot drag it to the Process window (I
understand<br>
> that the sensor configuration is also needed). I therefore drag
in the<br>
> Process window any data associated with the subject. Is this
correct? Does<br>
> the program then automatically process the segmented anatomy?<br>
<br>
Yes, this is what you should do: select some recordings for the
subject, and it will get the files it needs automatically from the
database.<br>
Right now, this process does the following:<br>
- If the segmented masks produced previously with ft_volumesegment
are available (called "<span class="pl-s">mask_innerskull", "</span><span
class="pl-s">mask_outerskull" and "</span><span class="pl-s">mask_scalp")
it uses them.<br>
- Otherwise it </span>uses the selected volume (displayed in
green), passes it to ft_volumesegment for segmentation, then uses
the segmented volumes without storing them anywhere.<br>
<a class="moz-txt-link-freetext" href="https://github.com/brainstorm-tools/brainstorm3/blob/master/toolbox/process/functions/process_ft_prepare_leadfield.m#L153">https://github.com/brainstorm-tools/brainstorm3/blob/master/toolbox/process/functions/process_ft_prepare_leadfield.m#L153</a><br>
<br>
<br>
Cheers,<br>
Francois<br>
<br>
<pre class="moz-signature" cols="72">--
François Tadel, MSc
MEG / McConnell Brain Imaging Center / MNI / McGill University
3801 rue University, Montreal, QC H3A2B4, Canada
</pre>
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