DICS

[Muthuraman Muthuraman]

Hello

Thanks for the suggestion to use the jackknife variance estimate it works
thanks a lot

To use the DICS method

We have a 64 channel EEG measurement from (Neuroscan) and 4 EMG channels
recording
and also we have the 64 channel measurement in FRMI

the electrode locations we have it in a file with 3 columns x,y,z for each
electrode
using the polhemus sensors but our own software

In the Source analysis
Cfg.method='DICS';
but Cfg.xgrid, ygrid and zgrid
the grid values are the sensor location values

or it should be the
cfg.grid.pos-where i can give in the 3 values [x y z] for each electrode

I am a starter in the source analysis in combining EEG-FMRI
please let me know

with regards
muthuraman.






>From: Robert Oostenveld <r.oostenveld at FCDONDERS.RU.NL>
>Reply-To: FieldTrip discussion list <FIELDTRIP at NIC.SURFNET.NL>
>To: FIELDTRIP at NIC.SURFNET.NL
>Subject: Re: [FIELDTRIP] query on confidence limit, DICS
>Date: Fri, 7 Jul 2006 12:36:02 +0200
>
>On 7 Jul 2006, at 12:04, Muthuraman Muthuraman wrote:
>>As i am able to sucessfully use the coherence analysis using  freq_mtmfft
>>and frq_mtmwelch to calculate the coherence
>>i would like to know is there a way to calculate the confidence  limit for
>>the coherence calculated from the freqanalysis, is there  a standard code
>
>You can compute a jackknife estimate of the variance in the coherence
>using the freqdescriptives function. That requires keeptrials=yes in
>freqanalysis.
>
>>Next, i would like to follow with the source analysis 'DICS' is  there a
>>tutorial available
>
>No there is no tutorial available specifically for that. You can look  at
>the beamformer tutorial at http://www2.ru.nl/fcdonders/fieldtrip/
>doku.php?id=fieldtrip:documentation:tutorial:beamformer, the relevant
>options are cfg.method=dics, cfg.refchan and/or cfg.refdip.
>
>Robert