Dear Ruth,
[log in to unmask] wrote:
> Hello SPM helpers,
> We did some preliminary analyses of PET O-15 data (5 subjects) some
> time back using SPM96 implemented under Unix and Matlab 4.2. Now we have
> collected more data (11 subjects) and we have installed SPM99 on Windows NT
> with Matlab 5.3.
> When re-analyzing the data (including realignment and normalization
> within SPM99) we seem to be getting quite different results. I believe the
> difference is at least partly due to SPM99 making the correction for time
> effects within session (scan number).
> I would like to compare the SPM96 and SPM99 analysis on the same
> datafiles, but we no longer have access to the Unix installation of SPM96.
> According to the SPM HELP files, it should be possible to access the SPM96
> format for setting up the design matrix. However I can't find the SPM96
> options on the menu for PET/SPECT analysis. Can you please tell me how to
> implement an SPM96 analysis for PET under SPM99?
>
As far as I know there is no "SPM96 mode" in SPM99. There are a number of
small changes between the analysis of PET data between SPM96 and SPM99 (even
though most changes affect mainly fMRI). Certainly the spatial preprocessing
has been changed (improved) and I would suspect that you will find different
results e.g. for realignment of data with large movements and for spatial
normalisation of noisy images.
In the stats section the main difference affecting you is that inferences are
now based directly on t-fields (rather than gaussianised t-fields).
However, the general design options available in SPM96 are all available in
SPM99, albeit with sometimes different names. There is certainly no "general"
time effects correction in SPM99. If you could just let us know what design
option you used in SPM96 (possibly a small tiff of the design matrix) I am
sure we could help you set up the same design with SPM99.
>
> Thank you in advance,
>
> Ruth Reinsel
Good luck Jesper
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