Dear HCP experts, I want to perform a seed-based (preferably probabilistic) tractography for some brainstem ROIs using the HCP 7T DTI dataset.
To do so, I used FDT probtrackx2 for every subject to calculate the ROIs streamlines. In order to do a group analysis (replicating the method here <http://dbic.dartmouth.edu/wiki/index.php/Diffusion_Tensor_Imaging_Analysis#Combining_Individuals_into_a_Group>), I created a binary pathways mask by puting the threshold#1 on each individual probabilistic map "fdt_paths.nii.gz". Then, I chose the threshold#2 for the summation of the individuals' binarized connectivity map to find the most recurring streamlines among subjects. The value of each "fdt_paths.nii.gz" voxel shows the accumulative number of streamlines from all the voxels under the ROI mask. Now, the issue is how to choose threshold#1, which is probably dependent on many factors; specifically the tracts length (and also maybe seeds location and volume?...). And a more basic question is if this whole approach makes sense at all, since no inferential statistics is being used? Thank you in advance. Best, Amin _______________________________________________ HCP-Users mailing list [email protected] http://lists.humanconnectome.org/mailman/listinfo/hcp-users
