Hi sear SPMers,
I'm calculating the lateralization index and I wonder how to realize:
(1) variable statisctical thresholds across subjects - for each
individual the selected threshold should correspond to a fixed number of
activated voxels in certain regions.
(2) mean activation of the 5% of voxels showing the highese level of
activation in certain ROI.
(3) % signal change analysis with a given threshold for inclusion (i.e.
only the voxels that exceed the given activation level are included to
calculate).
Reference: Jansen et al., 2006. The assessment of hemispheric
lateralization in functional MRI--robustness and reproducibility. PMID:
16904913
Your help will be very much appreciated!!!
Qing
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