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Jokel,

You can compute the residuals of your original blocked design using the following matlab commands:

load SPM;                                      % load in the SPM.mat
r = spm_sp('r', SPM.xX.xKXs, Y);     % get residuals

where Y is your extracted time-course.

Hope this helps,

Rich.



2009/12/6 Jokel Meyer <[log in to unmask]>
Dear SPM-experts!

I extracted a timecourse/signal (first eigenvariate) from a couple of regions of interest from a blocked design. However I would like to remove the task-related activation from this signal and there seemed to be to approaches:

1. Simply from the signal of each block substract the mean signal of this block. 

2. Deconvolve the signal by modelling task-related signal-changes with the help of the hemodynamic response function and regressing out task-related activation.

The first approach is of course quite easily scripted in matlab, however in the second case I would be very thankful for some hints how to implement this approach in matlab and with the help of spm's functions.

Many thanks for the help!
Jokel



--
Richard Masterton, PhD
Postdoctoral Fellow
Brain Research Institute