This is a different normalisation - this refers to simply normalising
the mean signal to be the same across session and/or subjects - this is
a necessary step for subsequent group stats. This is not the same as the
3D (within time series) intensity normalisation that you switched off in
the GUI (and is off by default).
Heidi
Lipton, Michael wrote:
> Hi,
>
> I have noticed that although I do not enable the option for intensity
> normalization, at the bottom of the FEAT Report webpage it reads:
> "mean-based intensity normalisation of all volumes by the same factor"
>
> Is this a different normalization? Is there a way to disable it? Would
> that be recommended or not?
>
> Thanks,
>
> Michael
--
Dr Heidi Johansen-Berg
Wellcome Trust Training Fellow
Oxford Centre for Functional Magnetic Resonance Imaging of the Brain
John Radcliffe Hospital
Headington
Oxford OX3 9DU
http://www.fmrib.ox.ac.uk/~heidi
Tel: 01865 222782
Fax: 01865 222717
email: [log in to unmask]
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