Dear Alexander,
Thanks very much for your answer. I was mainly asking because a
reviewer claimed that by using SPM99 instead of SPM5 one is
reducing the sensitivity of group analyses of functional imaging
data. I could certainly imagine this being possible, but I wished
to know if there was any empirical evidence of this. Again, thanks
very much for providing that empirical substantiation.
Best,
Eric
Quoting "Hammers, Alexander" <[log in to unmask]>:
> Dear Eric,
>
>
> 99 vs 2: yes, for ligand PET (single scans per subject, i.e.
> conceptually the same as an fMRI second level analysis). The
> second (SPM2) study is submitted - if you can wait a little I can
> hopefully let you have a reference.
>
> 5 vs rest: Impressionistically, it's again an improvement (we
> didn't expect otherwise ;-) ) - we don't have hard data yet but
> we have test case datasets (real data with histological
> correlates) which could be used to directly compare if you're
> very keen to have hard evidence or back up the impression with
> some numbers.
>
> All the best,
>
> Alexander
>
> -----Original Message-----
> From: SPM (Statistical Parametric Mapping)
> [mailto:[log in to unmask]]On
> Behalf Of Eric Zarahn
> Sent: 30 March 2006 03:13
> To: [log in to unmask]
> Subject: [SPM] SPM5 spatial normalization
>
>
> Dear John and Group,
>
> Does anyone have any empirical evidence, published or otherwise,
> that
> spatial normalization in SPM5 or SPM2 leads to better sensitivity
> in
> second-level analyses than in SPM99?
>
> Thanks,
> Eric
>
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