Dear Helmut / Jesper:
I see my rant may not have resonated as much as I'd hoped...
My comments were not meant to imply any deficiency in the SPM templates, and you
are correct that they are registered in MNI space, and so should be billed as
such. However, if you take a dataset and perform 2 registrations - 1 to EPI and
1 to the T1 template you would not get the exact same locations for your
activations. That said I don't know how far away from each other they would be
(probably a few mm). In direct answer to Jesper's question, what you suggested
is what we do- no matter what template in SPM we normalize to we call it MNI
space and have done so even for local templates based upon the SPM ones. My
comments were made only in relation to the state of anatomic normalization in
general, but this has been discussed in the past on the list.
Darren
Quoting Helmut Laufs <[log in to unmask]>:
> Dear Jesper,
>
> as John has still not answered (at least not to the list), please take
> another view from an amateur:
>
> to my knowledge (here we go... :-) ) all templates provided by SPM(2) are in
> coregistration with oneanother, and particularly in MNI space (this would
> follow from the T1 being in MNI...).
>
> I have [implicitly] sold it as such in ms.
>
> Hope this is correct.
>
> Helmut
>
>
> ----- Original Message -----
> From: "Jesper Andersson" <[log in to unmask]>
> Sent: Wednesday, September 21, 2005 12:28 PM
> Subject: "Sort of Talairach"? "Talairachish"?
>
>
> > Dear John and others,
> >
> > I have a question regarding how we should describe the space instantiated
> > by the SPM2 EPI template. When using one of the MNI templates it seems to
> > be quite accepted to write something like "The Talairach space as defined
> > by the MNI template". How should we refer to the space that is defined by
> > the EPI template? Correct me if I'm wrong, but isn't this template based
> > on a large handful (10-15?) subjects scanned with the old 2T FIL scanner,
> > and certainly can't be referred to as the MNI space.
> >
> > We tried to pass it off as "approximate Talairach space", but got smacked
> > on our fingers by the reviewer for being too inprecise. Any thoughts
> > anyone?
> >
> > Puss Jesper
> >
>
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