Hi,
could one connect the EEG caps to the MEG machine through an extension
cable, for impedance measurements only? If I'm not completely wrong, simple
copper wires have resistances of <1Ohm/m, which shouldn't affect the
impedance measurement too much.
This would make impedance measurements at least a little bit easier and
more comfortable for the subjects...
Regards,
Olaf
>Date: Tue, 14 Aug 2007 12:31:26 +0100
>To: [log in to unmask]
>From: Olaf Hauk <[log in to unmask]>
>Subject: EEG impedance measurements
>
>
>Hello,
>
>impedances of EEG electrodes can only be measured with the Neuromag
>software while the subject is wired up to the MEG inside the MSR. This is
>uncomfortable for the subject and can delay preparation time. One solution
>would be to use a hand-held impedance meter to check impedances outside
>the booth.
>
>Ideally, we would like to be able to see impedances for all electrodes
>simultaneously on a screen while preparing the subject, as is usually the
>case for standard EEG measurements. I was wondering whether there is a
>commercial system for that purpose (independent of EEG amplifiers), or
>whether anyone has already come up with a DIY solution.
>
>
>Regards,
>
>Olaf
>
>
>--------------------------------------------------------------------------------------------------------------------
>
> Olaf Hauk
> Medical Research Council
> Cognition and Brain Sciences Unit
> 15 Chaucer Road
> Cambridge, CB2 7EF
> England
> tel.: +44 (0) 1223 273702
> fax: +44 (0) 1223 359062
> email: [log in to unmask]
>
> http://www.mrc-cbu.cam.ac.uk/
> http://www.mrc-cbu.cam.ac.uk/EEG/
> http://maia.mrc-cbu.cam.ac.uk/people/people-pages.php?id=57
--------------------------------------------------------------------------------------------------------------------
Olaf Hauk
Medical Research Council
Cognition and Brain Sciences Unit
15 Chaucer Road
Cambridge, CB2 7EF
England
tel.: +44 (0) 1223 273702
fax: +44 (0) 1223 359062
email: [log in to unmask]
http://www.mrc-cbu.cam.ac.uk/
http://www.mrc-cbu.cam.ac.uk/EEG/
http://maia.mrc-cbu.cam.ac.uk/people/people-pages.php?id=57
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