[Neuroimaging] slice timing check

[Christophe Pallier]

Hello,

I am trying to check various implementations of slice timing correction,
including the pure python version in pypreprocess.

To this end, I have written a python script (attached) to generate a
sinewave 'activation' pattern shifted along the z axis.

The result (`sinewave.nii`, included in the attached zip file) looks fine.

However, when I run the slicetiming correction with SPM (ot for that matter
pypreprocess), with what I believe are the correct parameters, the delays
of the various slices are not corrected as I would have expected (see
asinewave.nii: I would have expected the z delays to be corrected and the
image to be essentially uniform; the parameters for SPM are simply TR=1s,
slice order=ascending; 40 slices)

I apologize because this is not really a Python question, but if I solve
the issue, I may be able to convince colleagues that the pure python slice
timing correction in pypreprocess is doing the right thing. So, basically,
I hope that someone points out my mistake.

Best,


-- 
--
Christophe Pallier <christophe at pallier.org>
INSERM-CEA Cognitive Neuroimaging Lab, Neurospin, bat 145,
91191 Gif-sur-Yvette Cedex, France
Tel: 00 33 1 69 08 79 34
Personal web site: http://www.pallier.org
Lab web site: http://www.unicog.org
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