On Fri, 11 Jun 1999, John Ashburner wrote:
> SPM'96 could create normalized images of whatever dimensions you asked.
> By default however, it produced images with a bounding box of:
> -78:78mm in the x direction, -112:76mm in the y direction, and -50:85mm
> in the z direction. The default voxel size was an isotropic 2mm.
>
> If the spatially normalized image trims off bits of the brain that you
> are interested in, then you need to extend the bounding box. Alternatively,
> if you are just interested in a limited region of the brain, then you can
> specify a bounding box that just covers that region.
>
Dear John:
I must admit I was not clear enough when I posted the question. I always
had the impression that the template used by SPM'95 (PET image with
deleted skull called spm.img) corresponded to the bounding box used by
SPM'95. The Maximum Intensity Projections printed out by SPM'95, had
numbers that delineated the boundaries of the bounding box.
SPM'96 does not print any numbers at the boundaries of the box. But the
Maximum Intensity Projections look very similar to the ones in SPM'95 -
the box does not extend beyond the contour of the brain. This makes sense
since the Talairach atlas should be the same regardless of which bounding
box was used. The grid that is printed on the MIPs, corresponds to the
grid of standard Talairach atlas with dimensions (-64;64), (-104;68),
(-28:72). So my question is: do the MIPs retain these dimensions even
if a differentnbounding box was used at spatial normalization?
Many thanks,
--Vitaly Furman
Brain Imaging Lab
Columbia-Presbyterian Medical Center
New York, NY
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