You can sum them together. What matters is just where the image is
non-zero so you need to also possibly threshold to get the right set
of patches.
Vladimir
On 9/27/12, Jun Wang <[log in to unmask]> wrote:
> Dear Vladimir,
>
> thanks for your quick reply. On follow up question, can I have several
> priors since I have two significant short window MSP solution, one is after
> stimulus onset, one is before stimulus onset.
>
> best
> Jun
>
> On Thu, Sep 27, 2012 at 1:58 PM, Vladimir Litvak
> <[log in to unmask]>wrote:
>
>> Dear Jun,
>>
>> Yes what you did is correct. For source extraction from the whole
>> window you could try choosing MMN option and then adding the image you
>> got from the short window as fMRI prior.
>>
>> Best,
>>
>> Vladimir
>>
>> On 9/27/12, Jun Wang <[log in to unmask]> wrote:
>> > Dear SPM experts,
>> > I am doing source reconstruction on the ERPs from an auditory EEG
>> > study. Each subject was coregistered with his own MRI. Then I did group
>> > inversion. for inverse time window, previous discussion suggested
>> limiting
>> > time window around significant cluster based on sensor level analysis.
>> > It
>> > did help since I got strange strong center brain activation when I did
>> > source reconstruction for whole trial(-1000ms to 400ms). see F2.jpg.
>> When
>> > I limited reconstruction from 0 200ms, I got auditory cortex activation
>> > as expected.
>> > My questions are:
>> > 1) Is what I did correct?
>> > 2) What if I also want to extract source in auditory cortex from
>> -1000ms
>> > to 400ms, then seems I have to do source reconstruction during whole
>> time
>> > window. This approach seems inaccurate based on above results. How
>> > could
>> I
>> > compromise this issue.
>> >
>> > Thanks for your feedback,
>> >
>> > Best,
>> >
>> > Jun
>> >
>>
>
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