[Eeglablist] Lowpass filtering after preprocessing

[Andreas Widmann]

Hi Eric,

I recommend not to filter epoched data unless absolutely necessary. Any filter implementation has to extrapolate the signal at the (epoch) edges the one or the other way possibly introducing edge effects depending on the signal and extrapolation algorithm (possibly also affecting phase). Edge effects are indeed usually less pronounced and problematic for lowpass filters than for highpass filters but cannot be excluded in general.

Hope this helps! Best,
Andreas

> Am 27.02.2017 um 18:18 schrieb Eric HG <erichg2013 at gmail.com>:
> 
> Hi everyone,
> 
> Is there any problem to perform lowpass filtering after preprocessing when preprocessing includes the following: 
> High- and low-pass filtering, cleanline, epoching, removal of epochs, average referencing and ICA?
> 
> Thanks a lot,
> 
> Eric
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