Just a follow-up on this...
In a group analysis, the bg_image created seems to have different
coordinates from the
avg152T1 atlas which it was registered to. That is, when functional
data is overlaid on the
bg_image the peaks come out off by 2 mm in the X direction, 4 in the y
direction, and 2 in the
Z direction relative to what is reported in the cluster list. However,
when the functional data
is overlayed on the avg152 atlas, the coordinates from the list match
where the peaks are. Why
would the bg_image have different coordinates if everything is
registered to the standard
space during a group analysis?
Thanks,
Jonas
On Jun 25, 2004, at 7:33 AM, Stephen Smith wrote:
> Hi - they should correspond in general - if you look at a first-level
> analysis and look at the non-Talairach-space version of the cluster
> table,
> the voxel positions should correspond to the voxel positions shown in
> FSLView. Does this work for you? The only minor issue might be that
> FSLView is about half a voxel out when showing standard-space images
> and
> reporting mm co-ordinates - that'll get fixed in the next version.
>
> Cheers, Steve.
>
>
>
> On Fri, 18 Jun 2004, lucina wrote:
>
>> Hi, I have a question about FSL view: In trying to locate the peak
>> voxels, I used the local maxima table that you can find in the
>> report.html for each contrast. However, it seems that the coordinates
>> listed there don't match up with the actual peaks I can see in FSL
>> view. In other words, the coordinates listed in the tables don't
>> correspond to the peak activations in FSL view. Any ideas? Thanks,
>>
>> Lucina
>>
>> --
>> Lucina Q. Uddin
>> UCLA Psychology-Cognitive Neuroscience
>> Box 951563, B627 Franz Hall
>> Los Angeles, CA 90095-1563
>>
>
> Stephen M. Smith DPhil
> Associate Director, FMRIB and Analysis Research Coordinator
>
> Oxford University Centre for Functional MRI of the Brain
> John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
>
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
>
>
--
Jonas Kaplan , Ph.D.
Ahmanson-Lovelace Brain Mapping Center
University of California, Los Angeles
Los Angeles, CA 90095-1553
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