[FieldTrip] problem ft_freqanalysis

["Jörn M. Horschig"]

Hi Bart,

it might help if you paste the code that you are using for computing the 
FFT and for plotting. Also, showing the structure (e.g. fieldnames and 
size of the content) might help.
Generally, the problem could just be related to huge 1/f noise and that 
you need to zoom in to see modulations of higher frequencies. Hard to 
tell though without any further information on what you are exactly doing ;)

Best,
Jörn

On 10/12/2013 6:15 PM, Bart Michiels wrote:
> After using ft_freqanalysis for EEG resting-state data I am unable to 
> see the whole spectrum of my data, which should show some content 
> between 0 and 60 Hz. I only see some low-frequency content (between 0 
> and 8 Hz) when using plot(...).
>
> Pre-processing steps:
> Avg re-reference, BP filter 0.25-100, cut continuous data into 4s 
> segments, resample data to 512 Hz, detrend, re-reference (after avg 
> rereferencing) to the A1&A2 electrode, Artefact rejection 
> (max=80,min=-80,range=160, default jump artefact algorithm), visual 
> inspection of the data. There are three datasets of 1 patients (every 
> dataset cut into 4s segments). After preprocessing, those data sets 
> are merged with ft.appenddata.
>
> I tried everything (wavelet, multi-taper), I always have the same 
> result, can someone tell me what I am doing wrong?
>
> Bart Michiels, Research Assistant.
>
>
> _______________________________________________
> fieldtrip mailing list
> fieldtrip at donders.ru.nl
> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip


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

P.O. Box 9101
NL-6500 HB Nijmegen
The Netherlands

Contact:
E-Mail: jm.horschig at donders.ru.nl
Tel:    +31-(0)24-36-68493
Web: http://www.ru.nl/donders

Visiting address:
Trigon, room 2.30
Kapittelweg 29
NL-6525 EN Nijmegen
The Netherlands

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20131014/df24540a/attachment.html>