Anupa,
there is loads of information on the preferred order of steps in the
literature, the spm manual, and the archives.
For some situations, there is no consensus, but several suggestions have
been supplied. Generally, you want to reslice in as few steps as
possible as every time, you will have to interpolate your data which,
put simply, is bad. It is unavoidable at some steps (slice timing, for
example, or realign and unwarp) but the aim should be to avoid it if
possible.
And more concretely, no, you should not do it before the other steps, it
is not necessary and, for the reasons stated above, harmful.
Cheers,
Marko
Anupa AV wrote:
> Dear SPMers,
>
> If I want to reslice the fMRI images, should that be the first step of
> the pre-processing step?
>
> To be more clear, is it ideal to do other preproc. steps like realign,
> slice timing, coregister...etc, after reslicing to the desired voxel?
>
>
> On Monday, February 23, 2015 7:49 PM, Anupa AV <[log in to unmask]> wrote:
>
>
> Dear Guillaume,
>
> Thanks a bunch...
>
>
> On Monday, February 23, 2015 7:11 PM, Guillaume Flandin
> <[log in to unmask]> wrote:
>
>
> Hello,
>
> you don't need to change the resolution of your images and it is OK to
> have non-isotropic voxel sizes.
>
> If, for some reasons, you have to reslice your images at a different
> resolution, you might want to look at this piece of code:
> https://en.wikibooks.org/wiki/SPM/How-to#How_to_change_the_voxel_size_of_an_image.3F
>
> Best regards,
> Guillaume.
>
>
> On 23/02/15 12:02, Anupa AV wrote:
> > Dear SPMers,
> >
> > The voxel dimension of my fMRI images are 2/2/6 mm.
> > When we do a native space based fMRI, is it very necessary to reslice
> > the fmri images to 2/2/2 mm?
>
> >
> >
> >
>
> --
> Guillaume Flandin, PhD
> Wellcome Trust Centre for Neuroimaging
> University College London
> 12 Queen Square
> London WC1N 3BG
>
>
>
>
>
--
____________________________________________________
PD Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
[log in to unmask]
http://www.medizin.uni-tuebingen.de/kinder/epn/
____________________________________________________
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