Was that the max listed in FSLView, or a max you found by using fslstats
<pathway> -R? The latter is the correct maximum for a pathway, what is
displayed in FSLView may not be correct.
Peace,
Matt.
-----Original Message-----
From: FSL - FMRIB's Software Library [mailto:[log in to unmask]] On Behalf
Of Conrad Rockel
Sent: Wednesday, November 12, 2008 3:58 PM
To: [log in to unmask]
Subject: [FSL] probtrackx intensity is 4?
Hi there,
I have just run several different subjects using a single seedmask and 2
waypoint masks using the probtrackx in FSL version 4.1.1 (centos5-32bit).
While I understand the concept that track intensity is a reflection of the
number of tracks running through it (#voxels in seed x 5000), every single
output had a max intensity of 4. I know I'm reliable, but I can't possibly
be
that consistent! Furthermore, the max of 4 was listed inspite of the
apparent
robustness of the track, and even in cases where no tracks were produced at
all.
When I move the outputs to another machine running a slightly earlier
version
of FSL, this max=4 is maintained, leading me to suspect it may be a
bedpostx/probtrackx problem rather than a problem with FSLview. At first I
thought it may be scientific notation, until tracking with another FSL
version
actually produced track intensity maxima stated in scientific notation.
Finally, I occasionally got a eerily consistent error on the earlier version
(4.0),
although this time, the value was 3.0008, 1.0001, or 1.0004.
Any ideas what this could be due to?
Thanks,
Conrad
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