Hi Peter,
>So my question was rather: does everybody agree
>on the conclusions of this paper or are there procedures, post-processing
>or other, such as shimming, choice of slices and angles, that have proven
>effective in minimizing the problem to such an extent that fMRI is at
>least as good as PET in scanning ventral temporal regions.
>From discussions with our physicists, it sounds like there are things
one could do to reduce the macroscopic susceptibility artifacts --
particularly if you
are specifically interested in one region. If the lateral surface of the
ventral temporal region
if the area you are most interested in, you can often use manual shimming
to reduce the
field gradients in that region. The problem is that this typically
distorts the signal from other
areas but if you are doing an ROI analysis, this may not be important.
Obviously, using a
small volume statistical correction for this region will further increase
your sensitivity.
It may be worthwhile piloting your experiment with one or two subjects in
fMRI and
looking at their data before deciding further.
Best of luck,
Joe
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