[FieldTrip] Questions on High pass and Dft filtering

["Jörn M. Horschig"]

Hi Philipp,

> The padding ensures that we only filter out a narrow 1/10 Hz wide 
> frequency bin.

sure, I didn't think about that - that's a pretty good reason to use 
padding :) However, the estimation of the 50Hz noise will be biased by 
the padded samples. I don't like the dftfilter anyway, and I am not 
filtering either (the reason for me is that 50Hz noise should be 
invariant to the experimental effects. I mostly investigate TFRs).

>   but looking at averaged timelocked data for the subject, the data looks
>   identical to the result I get using no filter at all, i.e., contaminated by
>   strong line noise.

I'm gonna look into this to see whether it is a bug or not. I'll let you 
know soon.

Best,
Jörn





-- 
Jörn M. Horschig
PhD Student
Donders Institute for Brain, Cognition and Behaviour
Centre for Cognitive Neuroimaging
Radboud University Nijmegen
Neuronal Oscillations Group

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