Hi all
Here by cross correlation, I mean just use a signal (e.g. a box-car
function, or a time course) to correlate the whole brain bold signals
directly. The cross correlation is explicitly implemented in other software
such as afni and brainvoyager but not in spm.
But spm is supposed to be able to do such a simple analysis. I figure that
in the first level step, input the signal to be correlated as a "regressor",
just like head motion parameters, meanwhile, there is no need to define
"conditions". Which will do a cross correlation. Also, multiple signals
could be input at the same time as "mutiple regressors", so several cross
correlation can be performed together. Can somebody with experience let me
know whether I am correct?
Thanks.
xiang
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