[Eeglablist] coregistering measured electrode positions

[Arnaud Delorme]

Dear Igor,

pop_chancenter simply centers channels and coregister allows moving channels in 3-D, rotating them and stretching them. So coregister does not need channel centering preprocessing (neither for source localization or 3-D head plots). Nevertheless, you might want to perform channel centering so channels are more evenly distributed in you 2-D scalp maps.

Best,

Arno


On Jun 10, 2011, at 9:40 AM, Igor Riecansky wrote:

> Dear EEGLAB Developers and Users,
>  
> After importing measured electrode position to an EEGLAB data set these location data are processed in order to adjust them with the 2-d head model using functions pop_chancenter() and forcelocs(). For the purpose of source localization, electrode positions must be aligned with the 3-d head model. This is done with the function coregister(). My question is, which location data should be entered for coregistering, original measured positions or positions adjusted by pop_chancenter()? In my opinion, original real measured positions must be used not adjusted locations, but this is not stated explicitly in the documentation.
>  
> Thank you in advance for comments on this issue.
>  
> Best whishes,
>  
> Igor
>  
>  
>  
> ------------------------------
> Igor Riecansky, MD, PhD
> Laboratory of Cognitive Neuroscience
> Institute of Normal and Pathological Physiology
> Slovak Academy of Sciences
> Sienkiewiczova 1
> 813 71 Bratislava, Slovakia
> Tel.: +421-2-52 92 62 75
> Mobile: +421-908-419 712
> Fax: +421-2-52 96 85 16
> www.unpf.sav.sk
>  
> _______________________________________________
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to eeglablist-unsubscribe at sccn.ucsd.edu
> For digest mode, send an email with the subject "set digest mime" toeeglablist-request at sccn.ucsd.edu

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sccn.ucsd.edu/pipermail/eeglablist/attachments/20110621/e6d0e4d0/attachment.html>