[Eeglablist] When to perform re-reference?

Jerry Zhu jerryzhu at siu.edu
Wed Jun 18 15:45:47 PDT 2014


Hi Makoto,
Thank you again for your reply.

Did you mean "averaging AFTER removing bad epoches" in your sentence "you
should apply average referencing AFTER removing bad channels."?

So here are my processing:
1) re-reference  (from Cz to average in my case)
2) remove bad epoches
3) interpolate bad channels
4) ICA

Sounds like you would recommend the order: 2143?

Looking forward to your and others inputs!
Thanks all!
Jerry

--
Jian Zhu, M.A.
Brain and Cognitive Sciences
Department of Psychology
Southern Illinois University Carbondale
Web: http://zhupsy.com

We have two halves in the brain: left and right. Nothing is right in the
left. Nothing is left in the right.


On Wed, Jun 18, 2014 at 1:38 PM, Makoto Miyakoshi <mmiyakoshi at ucsd.edu>
wrote:

> Dear Jason,
>
> I remember you said that average reference should be applied before ICA,
> but I did not understand exactly why. Could you comment on this?
>
> Jerry, you should apply average referencing AFTER removing bad channels.
>
> I don't think it makes big differences between average referencing before
> or after interpolation. However we don't necessarily recommend
> interpolation before ICA.
>
> Makoto
>
>
> On Tue, Jun 17, 2014 at 12:20 PM, Jerry Zhu <jerryzhu at siu.edu> wrote:
>
>> Hi all,
>> At which stage do you re-reference your data? It was suggested do re-ref
>> before ICA (http://sccn.ucsd.edu/pipermail/eeglablist/2011/003795.html).
>> How about re-ref before/after bad epochs rejection and bad channel
>> interpolation? The note here  (
>> ftp://ftp.egi.com/pub/documentation/technotes/SplineInterpolation.pdf)
>> suggests after interpolation. ("Since the interpolated potentials can be
>> used to better approximate the average reference (Junghofer et al., 1999),
>> it may be somewhat advantageous to compute the interpolated potentials
>> directly from the measured data, in which case the voltages below are best
>> thought of as referring to these measured potentials")
>>
>> What is your experience? Thanks for your sharing and suggestions!
>>
>> Jerry
>> --
>> Jian Zhu, M.A.
>> Brain and Cognitive Sciences
>> Department of Psychology
>> Southern Illinois University Carbondale
>> Web: http://zhupsy.com
>>
>> We have two halves in the brain: left and right. Nothing is right in the
>> left. Nothing is left in the right.
>>
>> _______________________________________________
>> 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" to
>> eeglablist-request at sccn.ucsd.edu
>>
>
>
>
> --
> Makoto Miyakoshi
> Swartz Center for Computational Neuroscience
> Institute for Neural Computation, University of California San Diego
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sccn.ucsd.edu/pipermail/eeglablist/attachments/20140618/58a9888d/attachment.html>


More information about the eeglablist mailing list