Hi Ghazal,
> fro the mailing list I understood that there had been a few of you having the same question as mine, however I couldn't get an exact answer to it.
That may be because there is no exact answer :)
> I am using TOM template to create a group specific template based on the data from NIH study (that I suppose works the best for a group of 42 8-11 year old children). and I used that template in normalization step during preprocessing. it goes without saying that there is no meaningful dependence or relation between this template and the known template for adults (e.g. MNI template) and it makes the interpretation of the activation spots quite tricky!! since I cannot use the coordinates given by SPM and look them up in available brain atlases to find the anatomical point for activation. (as these atlases are all based on adults brains)
I agree: the whole point of using a custom template is to be have more
appropriate reference data for your group under study. When using such a
template, you bring the images into (in SPM's case) MNI space, but they
are not necessarily in alignment with the templates that were used to
generate automatic lookup-helper-applications (although they may not be
very far off, either). Note that this issue is by no means one of the
TOM approach but will apply to each and every study using customized
templates. I see that the famous Good et al paper (NI 2001) has been
cited about 1500 times, and if all of them used the there-described
approach to creating a custom template... you get my point.
> sop how can I report about the anatomical point of activation. i am not very good at anatomy too look at the activity and guess the name of that point. even if I was that wouldn't be scientifically accepted I suppose
I agree that guessing is not a good idea but I do not see why it should
not be scientifically acceptable to use your eyes. Actually, I think
that it may be less scientific to feed a long row of numbers into an
algorithm and take the results at face value without checking at least
some of them, using common sense and an anatomy textbook. The good thing
is that the images may speak for themselves, so including representative
slice that allow the reader to assess the localization goes a long way
(you should still be able to name the structures involved, though :). I
have written long paragraphs in a number of revisions, not all of them
successful, trying to convey may unwillingness to include a table of
activation foci, because, yes, this makes meta-analyses harder. But it
is a compromise, and somehting's got to give.
Cheers,
Marko
--
____________________________________________________
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
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http://www.medizin.uni-tuebingen.de/kinder/epn
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