<p dir="ltr">During Neuromag EEG acquisition usually there is a reference electrode placed on the nose. You could check the digitization field in the measurement information info['dig'] or look at any EEG channel info['chs'][eeg_idx]['loc'], IIRC the first three numbers are the digitized electrode location XYZ and the next three are the digitized reference location XYZ in head coordinates.</p>
<p dir="ltr">HTH,<br>
Eric</p>
<div class="gmail_quote">On Jul 9, 2016 1:19 PM, "Alexandre Gramfort" <<a href="mailto:alexandre.gramfort@telecom-paristech.fr">alexandre.gramfort@telecom-paristech.fr</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">sorry no idea<br>
<br>
A<br>
<br>
On Sat, Jul 9, 2016 at 1:29 PM, <a href="mailto:brainz@sina.com">brainz@sina.com</a> <<a href="mailto:brainz@sina.com">brainz@sina.com</a>> wrote:<br>
> Thanks, Alex,<br>
><br>
> I have learned the tutorials.<br>
> But do you know what is the original reference of the EEG sample data?<br>
> I noticed that<br>
> the scalp map using average reference is different from that using original<br>
> one.<br>
><br>
> Best wishes,<br>
> Junpeng<br>
><br>
><br>
><br>
><br>
> From: Alexandre Gramfort<br>
> Date: 2016-07-09 18:28<br>
> To: Discussion and support forum for the users of MNE Software<br>
> CC: Huang yunzhiGardenia Elaine<br>
> Subject: Re: [Mne_analysis] which type of refence eletrode is used in MNE<br>
> sample data (EEG)<br>
> hi,<br>
><br>
> MNE uses by default average reference.<br>
><br>
> have a look at this tutorial<br>
><br>
> <a href="http://martinos.org/mne/dev/auto_tutorials/plot_eeg_erp.html" rel="noreferrer" target="_blank">http://martinos.org/mne/dev/auto_tutorials/plot_eeg_erp.html</a><br>
><br>
> HTH<br>
> Alex<br>
><br>
><br>
> On Sat, Jul 9, 2016 at 11:53 AM, <a href="mailto:junpeng.zhang@gmail.com">junpeng.zhang@gmail.com</a><br>
> <<a href="mailto:junpeng.zhang@gmail.com">junpeng.zhang@gmail.com</a>> wrote:<br>
>><br>
>> Dear MNE users,<br>
>> I also had a question related to the EEG processing.<br>
>> Which reference eletrode is originally used in the EEG included in sample<br>
>> data?<br>
>><br>
>> Thank you in advance.<br>
>><br>
>> Junpeng<br>
>> “海纳百川 有容乃大”<br>
>> “Live as you are dying, and never stop trying”<br>
>><br>
>><br>
>><br>
>><br>
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