using ica to get occipital component producing alpha in eyes-closed resting eeg

[Thomas Hartmann]

hi,
i am looking for a method to identify the component(s) of an eyes-closed
resting-state eeg producing occipital alpha in a single subject. so far,
no method i tried (fastica, sobi) was able to produce such a component,
although topoplots show them very clearly. i also tried to filter the
data using a bandpass filter before letting the ica run.

i have 5 minutes of data available, partly contaminated with
tms-artifacts which i remove beforehand.

does someone know a good and stable approach? maybe i would have to
change the ica-algorithm? is there one specifically looking at
frequency-information?

maybe i also use the wrong approach? is there a different option to get
something like a weighting matrix restricted to a specific
frequency-band (and also able to seperate occipital alpha from other
alpha generators like, e.g. temporal, motor etc..)?

thanks in advance!
greetings,
thomas

--
Dipl. Psych. Thomas Hartmann

OBOB-Lab
University of Konstanz
Department of Psychology
P.O. Box D25
78457 Konstanz
Germany

Tel.: +49 (0)7531 88 4612
Fax: +49 (0)7531-88 4601
Email: thomas.hartmann at uni-konstanz.de
Homepage: http://www.uni-konstanz.de/obob

"I am a brain, Watson. The rest of me is a mere appendix. " (Arthur Conan Doyle)

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