2D plots of ecog data

Hi everyone,
I’m working with ecog grids and I would like to use plot_evoked_topomap to see my data. I have the 2D coords of my sensors.
Unfortunately, ecog channel type is not supported by topomap function (is it?), so I would like to fool it by changing channel types into EEG type (in the evoked object). So my question is: how do I do this? Is there a “set_channel_type” or something that could do the job?
many thanks for your help !

ps : 3D views look fine too, but I don’t have freesurfer meshes (I don’t have direct acces to these clinical data), this is why 2D maps is clearly the “optimal” option right now… :wink:

Hello @flecaignard and welcome to the forum! I’m tagging @adam2392 and @mainakjas, I believe they’re actively working with iEEG / ECoG data.

also tagging @alexrockhill

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in the meantime, there is a method set_channel_types, see the evoked docstring here or see here for an example with a Raw object,

It sounds like you’re trying to do something similar to this example Working with ECoG data — MNE 0.23.dev0 documentation. Is there something in the example that’s lacking or that is incompatible with your setup?

Hi Alex and all, thank you all for your prompt responses
I don’t have cortical meshes in the freesurfer format, I only have matlab files with nodes and edges basically. I clearly consider adjusting the code but this will be later, right now, 2D maps will be fine to see my data … :wink:

Thanks Dan
I’m sorry I did not see this function yesterday … :roll_eyes:
I’ll try but I think this is what I need

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Yeah, if you don’t have the freesurfer recon, you could try aligning the positions to fsaverage but that would just be an estimate. Or, if you have them in 2D, you could just pick up with the tutorial after the image of the montage.

Hi there,
Thanks Alex for the advice, I’ll try this
Regarding my 2D maps, I face a projection trouble (I guess). Precisely, here is the layout I made, which is correct :

Then, using this layout in plot_evoked_topo, I get this, which is correct (and cool!) :slight_smile:

but when I use plot_evoked_topomap, my sensors seem to have been transformed (projection on a sphere ?)

what do you think I should do ?
Many thanks (again!)

And another question: how could I make the map bigger within the figure? I’ve played with res and size parameters but this would not really work, and yields bigger figure (rather than bigger map in the figure)

Many thanks+++

Capture d’écran 2021-04-22 à 10.54.56