I have some issues regarding the glass brain visualization in SPM5. I have
run a blocked design fMRI experiment, and done all the pre-processing
steps. 36 axial slices and about 280 volumes were acquired for each
participant (total 8)
The problem arise when I look at the results (fixed effects for each
participant): the glass brain visualization looks normal except there is a
thin slice of data missing in both the sagittal and coronal views, going
through the whole brain horizontally. This whole slice is white, e.g.
missing data. However, when I use the display - overlay function, the
activation map is complete.
I have checked the raw data, and the image files after each pre-processing
step. Up until the smoothing step (which is the last pre-processing step I
did), each participants functional data looks good (using the check-reg
function).
Also, when I import another dataset from a different experiment, the
glass-brain visualization of the results looks ok.
It seems to me that there is something with the glass-brain that is wrong,
since the overlay picture is ok. How can the two be different, don't they
use the same data (beta-weighted images) to display the results? Does
anyone know the source of this problem, and how to fix it? I guess it
doesn't matter since my data and results look good, but it is annoying not
being able to visualize the data using the glass-brain.
-Lasse
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Lasse Bang
Master Student - Cognitive Neuroscience
Department of Psychology - University of Oslo
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