Multitaper analysis

rion rion_raman at REDIFFMAIL.COM
Wed Aug 5 21:52:49 CEST 2009

Dear Fieldtrippers,

I am new comer to Fieldtrip.
I have a question on the Multitaper method (mtmconvol) when used on EMG signal analysis.

If i am right the method works in this way, the tapers are multipied with the data in the time domain
and then the tapered data is fourier transformed and the auto and cross spectra are calculated followed by the
averaging of the tapers.

The EMG in my case is rectified and then it has only positive values now the multiplication of
the tapers with the rectified EMG gives out some negative values due to the dpss tapers (For ex: 7 Tapers) in the time domain.
These negative values are not relevant to the EMG signal. How are these values used in the latter analysis.
I am missing something here any hint will be helpfull.

With regards,

The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also and
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