Hello Matt,
Thank you very much for your reply, I tried the script and
it works great.
I have one more question : I plan to draw 21 ROI's (one for each
patient) and obtain the % signal change values for each patient and then
average the values to obtain a single hrf curve for the group.
Just to make things a lot simpler is it possible to use a group average
design matrix from SPM with the ROI drawn on the group averaged anatomy
images and then obtain the % signal change for the group. I have tried
to use the group averaged SPM matrix but I don't think Marsbar accepts
it. If this method is possible, does it mean that the % signal change
curves obtained by both methods will be the same?
Thanks a lot in advance,
Binu Thomas.
Univ. of TX Southwestern Med. Center.
>>> Matthew Brett <[log in to unmask]> 01/02/06 5:36 PM >>>
Hi,
> I have a group of 21 patients on which I am
> extracting the hrf waveforms for different event types from an ROI.
I
> want to average the hrf's for all 21 patients so I have one hrf
waveform
> which represents the patient group. I am using the SPM design matrix
to
> specify the event types in Marsbar. I am planning on drawing an ROI
for
> each patient and then extracting the hrf's, is there any way to
avreage
> the hrf waveforms of all patients using Marsbar?
Not directly, but if you use something like the script in the FAQ:
http://marsbar.sourceforge.net/faq.html#extract_fir
you can extract the timecourses into a matrix, and average them using
matlab...
Best,
Matthew
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