If you are after area-wise activation in individual subjects, would you be 
willing to do a parcellated (i.e. area-wise) analysis where you could use 
something simple like FDR or Bonferroni (and get substantial SNR/power 
benefits)?  If what you are actually after is to define regions of activation 
(instead of assessing the statistical significance of the activation in every 
grayordinate), I wouldn't use statistical thresholding but instead would use 
gradients in the effect size map to identify most probably boundaries.

In most cases for multiple comparison correction we are recommending people to 
use FSL's PALM, but it is permutation-based.

Peace,

Matt.

From: 
<hcp-users-boun...@humanconnectome.org<mailto:hcp-users-boun...@humanconnectome.org>>
 on behalf of Julien Dubois <jcrdub...@gmail.com<mailto:jcrdub...@gmail.com>>
Date: Friday, October 9, 2015 at 4:53 PM
To: "hcp-users@humanconnectome.org<mailto:hcp-users@humanconnectome.org>" 
<hcp-users@humanconnectome.org<mailto:hcp-users@humanconnectome.org>>
Subject: [HCP-Users] Cluster-extent thresholding of CIFTI data

Dear HCP developers,

I'm wondering if you have come up with a good cluster-extent thresholding 
procedure and implemented it as part of the workbench yet. I have seen a couple 
of threads 
here<https://www.mail-archive.com/hcp-users%40humanconnectome.org/msg00893.html>
 and 
here<https://www.mail-archive.com/hcp-users%40humanconnectome.org/msg00993.html>
 re: this issue.

One strategy would be to go the Monte Carlo way, considering the two surfaces 
and the volume separately (cf. Hagler et al 
2006<http://www.sciencedirect.com/science/article/pii/S1053811906007919> for 
the surface, which seems to be implemented in Freesurfer as 
mri_mcsim<https://surfer.nmr.mgh.harvard.edu/fswiki/BuildYourOwnMonteCarlo> and 
mri_glmfit-sim for the surface; and of course the very popular 
AlphaSim<http://afni.nimh.nih.gov/pub/dist/doc/program_help/AlphaSim.html>, 
superseded by 
3dClustSim<http://afni.nimh.nih.gov/pub/dist/doc/program_help/3dClustSim.html>, 
in AFNI for the volume).

Another way would be to go the Random Field Theory route. It's done in the 
volume in SPM with spm_uc_clusterFDR.m; I'm sure it has been adapted to surface 
data in some software suites (looks like the matlab 
code<http://www.math.mcgill.ca/keith/fmristat/toolbox/stat_threshold.m> in this 
old 
thread<https://mail.nmr.mgh.harvard.edu/pipermail/freesurfer/2007-August/005881.html>
 could work).

Finally, FSL's randomize is another option that would play well with both 
surface & volume at the same time, and it seems to be the route you've taken. 
However (*correct me if I'm wrong*), this is not applicable to single-subject 
data with one run only, which is one of my interests.

Please advise on the current status of development, and whether I need to 
"hack" my own cluster extent threshold correction based on MC or RFT for CIFTI 
data (if anyone knows any other good code resources to perform these analyses 
on surface/volume data, please share!).

Thanks,
- Julien

--
Julien Dubois
Postdoctoral Scholar
California Institute of Technology, Pasadena, CA
http://emotion.caltech.edu/~jdubois

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