[Eeglablist] How to filter only EOG Channels?

[Hanna Kadel]

Dear EEGLab users, dear developers,

I would like to use a low-pass filter on selected channels of my EEG
data structure.  So far, I've used pop_eegfiltnew for data filtering,
but this applies the filter to all channels in the dataset. Is there any
possibility to apply a filter *only* to specified channels, leaving all
the other data unchanged? Or would I need to define my own filter
function for this purpose, or use some workaround with copying parts of
the dataset back and forth?

(Background: For rejection of eye-movement-contaminated trials, I use
VEOG and HEOG difference channels. Due to high frequency noise artifacts
in some recordings, I get a lot of "false positive" artifact trials.
Thus, I would like to low-pass filter the EOG-difference channels prior
to artifact detection)

Thanks a lot in advance for any hints & advice.

Hanna

-- 
Dipl.-Psych. Hanna Kadel
Philipps-Universität Marburg
Fachbereich Psychologie
Cognitive Neuroscience of Perception and Action
Gutenbergstraße 18
D-35032 Marburg

Tel: 06421 28-22160
E-Mail: hanna.kadel at staff.uni-marburg.de