topoplotTFR on planar gradients

[Ingrid Nieuwenhuis]

Dear Alex,

It looks as if you forgot to do combineplanar after freqanalysis, since
senstype is ctf275_planar. See
http://fieldtrip.fcdonders.nl/tutorial/eventrelatedaveraging#calculate_the_p
lanar_gradient for more info

Important to get planar gradient power data you should first calculate
planar gradient, then do freqanalysis and finally combine planar. (NOT first
combine and then freqanalysis, since the combined planar gradient is always
positive, and all frequencies will be messed up then)

Hope this helps,
Ingrid


> -----Original Message-----
> From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On
> Behalf Of Walther Alexander
> Sent: Sunday, August 09, 2009 5:35 PM
> To: FIELDTRIP at NIC.SURFNET.NL
> Subject: [FIELDTRIP] topoplotTFR on planar gradients
>
> Dear Fieldtrip Users,
>
> I'd like to apply the multiplotTFR function on freqstatistic results.
> The MEG raw data were converted to planar gradient scores and passed
> freqanalysis. Using fieltrip version 2008-12-08, the error message
> 'unsupported MEG sensor type' occurres which goes back to
> prepare_layout.m, line 880. Apparently, though senstype.m gets me the
> right information (ctf275_planar) that should be used to create an
> appropriate layout, prepare_layout ignores this and directly heads for
> the error message. Planar gradient settings seem to struggle somehow
> with grad2lay.m (line 259). If I switch to Fieltrip-20090803, it will
> create the plot thats attached. My configuration settings read as follows:
>
> cfg.maskparameter = 'mask';
> cfg.zparam = 'stat';
> cfg.interactive = 'yes';
> cfg.zlim = [-4 4];
> figure, multiplotTFR(cfg,data)
>
>
> Given unconverted raw data, everything works out well. Any advice?
>
> Cheers
>
> Alex
>
> --
> Alexander Walther
> Johannes-Gutenberg-University Mainz
> <awalther at uni-mainz.de>
>
> ----------------------------------
> 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
> http://listserv.surfnet.nl/archives/fieldtrip.html and
> http://www.ru.nl/neuroimaging/fieldtrip.

----------------------------------
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 http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/neuroimaging/fieldtrip.