Coherence and dipole

[Rodolphe Nenert]

Dear Jan, 

yes i do analyze EEG data. The data was recorded using vertex  (CZ) as 
reference, but i modified to an average reference before doing any time-freq 
analysis.

Rodolphe.

On Fri, 22 Oct 2010 09:04:00 +0200, jan-mathijs schoffelen 
<jan.schoffelen at DONDERS.RU.NL> wrote:

>Dear Rodolphe,
>
>I guess you are analyzing EEG data? What reference electrode(s) did
>you use?
>
>Best,
>JM
>
>
>
>On Oct 22, 2010, at 1:47 AM, Rodolphe wrote:
>
>> Dear Fieldtrip users,
>>
>> I recently run a coherence analysis on my data and i plotted a
>> beautiful Topographic plot showing a strong coherence between one
>> electrode in left parietal ( P5) and some right frontal electrodes.
>> The thing is, when i try with the right parietal equivalent ( P6 )
>> then i find a coherence with left frontal. Ans so on with a couple
>> of other electrodes use as ref channels.
>> As this symmetry looks awkward to me, is any of you have an idea of
>> a posible artifact that can cause this, or a possible bias in the
>> analysis? ( I tripled checked my code)
>>
>> Best,
>>
>> Rodolphe N., Ph.D.
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>
>Dr. J.M. (Jan-Mathijs) Schoffelen
>Donders Institute for Brain, Cognition and Behaviour,
>Centre for Cognitive Neuroimaging,
>Radboud University Nijmegen, The Netherlands
>J.Schoffelen at donders.ru.nl
>Telephone: 0031-24-3614793
>
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You are receiving this message because you are subscribed to
the  FieldTrip list. The aim of this list is to facilitate the discussion
between  users of the FieldTrip  toolbox, to share experiences
and to discuss  new ideas for MEG and EEG analysis.
See also http://listserv.surfnet.nl/archives/fieldtrip.html
and http://www.ru.nl/neuroimaging/fieldtrip.
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