Dear fsl users,
I have a dataset consisting of 2 groups of subjects (31 Controls- 17
Alzheimer's patients). The Alzheimer's dataset consists of T1 scans that
were taken 6 months after the "onset" of the disease. I did VBM analysis
using a kernel of 3 cause I was expecting small to intermediate changes
(since my scans depict an early stage of the disease) and after
fslvbm_3_proc, 4 volumes out of 48 were distorted. I excluded these 4 vols
from the GM_mod_merg_s3 files and continued with randomise choosing a
threshold of 3 for cluster size and cluster mass tests. Though my results
(tfce_corrp_tstat,clustere_corrp_tstat and clusterm_corrp_tstat) were really
strange revealing huge clusters covering 60-70% of the whole brain with very
high p-values < 0.003. It's not logical to expect such severe changes and I
cannot point out what went wrong in the analysis.
I would really appreciate your help.
Antonios-Konstantinos Thanellas
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