Question about electrode positions of a 64-ch EasyCap

Discussions
1

Dear Brainstorm team,

I am trying to record ERP data and estimate the sources using a 64-ch EasyCap and BrainProducts system. Can you please tell me why F9 and F10 electrodes, but not FT9 and FT10, are used at the TP9 and TP10 positions? I think, the flexibility regarding the position of the electrodes is an advantage of using EasyCap, but a standard design of, for example, 64-ch BrainCap and actiCap 64 (also actiCap 65 in your default cap), FT9 and FT10 are used.

Regards,
Masahiro
EasyCap_64channel.pdf (153 KB)

2

Dear Masahiro,

The EasyCap model currently in Brainstorm was submitted by Marco Buiatti (Neurospin, Paris).
I don’t know if this modification was done to match a specific montage they are using there.
Please see the following thread: http://neuroimage.usc.edu/forums/showthread.php?1276-easycap-64-channel-location-setup

If you are interested, you can take the current EasyCap from Brainstorm, and edit it to make it match your own setup:

  • Right-click on the channel file > Edit channel file: You can edit the name and order of the channels with this interface
  • Then right-click on the channel file > MRI registration > Edit, to edit the position of the electrodes (read the tooltips of the different buttons to see what you can do).
  • In the end, you have to make sure that the order of the electrodes in the channel file matches exactly the list of channels recorded with your EEG acquisition software.

Then you can send this updated version to me and I can include it in the general distribution.

Cheers,
Francois

3

Dear Masahiro,

as Francois says, I contributed the EasyCap model you are mentioning by matching the specific montage of my data. I have followed the very same indications that Francois is mentioning to you to add the F9 and F10 positions to a combination of the available setups (see http://neuroimage.usc.edu/forums/showthread.php?1276-easycap-64-channel-location-setup).

I have tried to match the F9 and F10 positions by hand following the standard extended 10-20 system (they are lateral to F7 and F8, respectively). There is no specific reason for which I have used these channels instead of others.

Hope this helps,

Marco

4

Dear Francois,

Thank you very much for your quick reply.
I will send a new version after it’s been made.

Regards,
Masahiro

5

Dear Marco,

Thank you for giving me the information.
I thought these electrodes were also used for horizontal EOGs.
Allow me to use your file as a reference to make a new file.

Regards,
Masahiro

6

Dear Masahiro (I read your reply only now),

sure, do edit it as Francois indicated, and let me know if there are any problems with that.

Best,

Marco

[QUOTE=Masahiro Hata;5878]Dear Marco,

Thank you for giving me the information.
I thought these electrodes were also used for horizontal EOGs.
Allow me to use your file as a reference to make a new file.

Regards,
Masahiro[/QUOTE]