I have a dataset from a event-related study which I am analysing using SPM8. I'm working my way through pre-processing of the data and have been using the steps in the 'Face data' example in Chapter 29 of the SPM8 manual.
The steps suggested in the example are: 1. Realignment (motion correction), 2. Slice timing correction, 3. Coregistration, 4. Segmentation, 5. Normalisation and 6. Smoothing.
In reading the recent thread on this list titled 'More Realign, Coreg questions' I noted Marko Wilke's advice to carry out realignment then coregistration using estimates only in each case and then do a single interpolation as part of normalisation.
In attempting to resolve these slightly conflicting sources of advice here I have two questions:
1. If I want to do slice-timing correction (which according to the explanation in the Huettel, Song and McCarthy text is necessary since my images were acquired using an interlaced acquisition order) but want to take Marko's advice to reduce the number of interpolations, should I do the slice timing correction before the realignment step?
2. Why is it that 'The authors of SPM do not generally suggest that [slice timing] correction be used'? (This question has been asked a couple of times recently but doesn't seem to have been answered).
Regards,
Barney
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Associate Professor Barney Dalgarno,
School of Education
Charles Sturt University
Wagga Wagga NSW Australia 2678
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http://csusap.csu.edu.au/~bdalgarn
Phone: 02 6933 2305
Fax: 02 6933 2888
Room: 27/118
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