custom topography for topoplotER

Thomas Thesen tnt at PHYSIOL.OX.AC.UK
Sun Jun 26 16:43:41 CEST 2005


Dear Ole & others,

Thanks a lot for your time in helping to figure out this problem. I greatly
appreciate it.

I have put an example data file (avg_ft_TT_S106Cond1.mat), the layout file
(iEEG_64.lay) and an image of the output figure of TOPOPLOTER
(topoplotER_iEEG_64.jpg) and MULTIPLOTER (multiplotER_iEEG_64.jpg  on the web:

http://www.physiol.ox.ac.uk/~tnt/fieldtrip/

I ran the following:

>> load avg_ft_TT_S106Cond1.mat

>> avg_ft_TT_S106Cond1

avg_ft_TT_S106Cond1 =

           cfg: [1x1 struct]
           avg: [64x2500 double]
           var: [64x2500 double]
       fsample: 1000
    numsamples: [70x1 double]
          time: [1x2500 double]
        dofvec: [1x2500 double]
         label: {64x1 cell}
         trial: [70x64x2500 double]
        dimord: 'trial_chan_time'

>>
>> cfg=[];
>> cfg.xlim = [0.5 1];
>> figure;
>> cfg.layout='iEEG_64.lay';
>> topoplotER(cfg, avg_ft_TT_S106Cond1);
reading layout from file iEEG_64.lay
selected 64 channels for plotting
>>

As you can see there is no error message but the topopgraphy is mapped onto
a circular headshape with ears and nose (see topoplotER_iEEG_64.jpg).

The actual data is recorded from an intra-cranial EEG electrode grid implant
on the superior temporal sulcus and has the following channel arrangement:

64 63 62 61 60 59 58 57
56 55 54 53 52 51 50 49
48 47 46 45 44 43 42 41
40 39 38 37 36 35 34 33
32 31 30 29 28 27 26 25
24 23 22 21 20 19 18 17
16 15 14 13 12 11 10 9
8 7 6 5 4 3 2 1

(The numbers correspond to the channels/sensors in avg_ft_TT_S106Cond1.avg)

Ideally, I would like to plot the topography on a 8x8 square (equal spacing)
instead of a round scalp. The layout file seems to be correct. If
MULTIPLOTER is used with the cfg configs:

>> cfg.layout='iEEG_64.lay';
>> figure;
>> cfg.xlim = [0.5 1];
>> cfg.axes = 'no';
>> cfg.showlabels ='yes';
>> multiplotER(cfg, avg_ft_TT_S106Cond1);
reading layout from file iEEG_64.lay

it produces a figure as in multiplotER_iEEG_64.jpg, and has the correct
sensor arrnagements.

cheers,

Thomas



On Sun, 26 Jun 2005 13:40:03 +0200, Ole Jensen <ole.jensen at FCDONDERS.RU.NL>
wrote:

>Hi Thomas,
>Please understand that our resources for support are limited; you can
>save us a lot of time by providing
>1) error messages
>2) the cfg settings you used
>3) your *.lay file
>I will then do my best to resolve the problem.
>Bests,
>
>Ole
>
>
>Thomas Thesen wrote:
>
>>Hi Robert, Eric & Others,
>>
>>I am trying to use TOPOPLOTER to make topographic plots of averaged
>>waveforms with interpolation between electrode positions.
>>
>>However, it seems that TOPOPLOTER uses a 2-D circular view of the head (with
>>nose & ears) as a a default plotting background structure. My data was
>>recorded from a 8x8 electrode grid (square and equal spacing). I made an
>>appropriate layout file (.lay), which works well with MULTIPLOTER, but not
>>with TOPOPLOTER.
>>
>>Any suggestions on how to make this work would be greatly appreciated.
>>
>>Cheers,
>>
>>Thomas
>>
>>
>>
>
>
>--
>Ole Jensen
>Principal Investigator
>F.C. Donders Centre for Cognitive Neuroimaging
>P.O. Box 9101
>NL-6500 HB Nijmegen
>The Netherlands
>
>Office  : +31 24 36 10884
>MEG lab : +31 24 36 10988
>
>Fax     : +31 24 36 10989
>
>e-mail : ole.jensen at fcdonders.ru.nl
>URL    : http://oase.uci.ru.nl/~olejen



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