Dear Duncan,
As I said, the most flexible solution at the moment is to export
everything to images and then combine them in any way you want with
imcalc. I'll try to find some time to look whether the montage
function can be changed to also support TF data.
Vladimir
On Tue, Dec 6, 2011 at 5:42 PM, Duncan Astle <[log in to unmask]> wrote:
> Thanks Valdimir,
>
> I can certainly relable the trials fine. However, when I average conditions together it does so on the basis of the channel number rather than my new labels - I.e. it is not actually forming contra and ipsilateral channels.
>
> Any idea how I could do this? Basically I want to average O1 from RVF trials with 02 from LVF trials and call it "O12contra", then average O2 from RVF trials with O1 from LVF trials and call is "O12ipsi" and so on for all channels. In short it needs to be more than just relabelling, I need to actually average different channels together. I guess this is why I used to use the montage operation for ERPs, and also why it worked.
>
> Any ideas of how to it with TF?
>
> Best,
> Duncan
>
> ________________________________________
> From: Vladimir Litvak [[log in to unmask]]
> Sent: 06 December 2011 11:06
> To: Duncan Astle
> Cc: [log in to unmask]
> Subject: Re: [SPM] Montage operations on TF data
>
> Dear Duncan,
>
> The montage function does not support TF data because what you want to
> do is not exactly what montage does in EEG (although this is just an
> aesthetic consideration and in principle this kind of operation can be
> done by multiplying with a montage matrix). What you can do without
> custom code is average a set of channels when you export to images and
> then combine those images in any way you want using imcalc. Renaming
> channels is quite easy either with the reviewing tool or with:
>
> D = spm_eeg_load;
>
> D = chanlabels(D, [1, 2], {'whatever1', 'whatever2'} );
>
> save(D);
>
> Best,
>
> Vladimir
>
> On Tue, Dec 6, 2011 at 8:36 AM, Duncan Astle <[log in to unmask]> wrote:
>> Dear all,
>>
>> I have done a nice TF analysis, looking at alpha power in spatial attention.
>> However, I want to change my montage, such that the electrodes are
>> relabelled into Contra and Ipsilateral, and then average contra left and
>> right, and ipsi left and right. This works fine for ERPs, but for some
>> reason I can't get it to work for TF data.
>>
>> I get an error message saying that you can't do montage operations on TF
>> data...... why is this!? and is there anythign I can do to change it?
>>
>> Any advice would be very very helpful.
>>
>> Best,
>> Duncan
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