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(Not updated in 2015) How to quantify results for FSL FIRST, after stats have been generated.

Clusters

For a stats file "L_Hipp_vertexMNI_rand_tfce_p_tstat1.nii.gz" for example, you can get information based on standard FSL reporting (this page has several examples).

The following two commands will get you started:

Defining clusters (see FSL guide)

Example command for corrected p value < 0.05 (which requires a threshold of 0.95 since p values are stored in nifti files as 1-p):

...

Tip: if you copy the table and paste into Excel, either from the Linux terminal or from the text file, it will sort into columns properly:

P values and t statistics

Example command to extract t values at significant clusters:

[datauser@localhost temp]$ cluster -i L_Hipp_vertexMNI_rand_tfce_corrpp_tstat1.nii.gz -t 0.95-L_Hipp_vertexMNI_rand_tstat1.nii.gz scalarname="1-p" > cluster_p1.txt  {optional: > cluster_corrp.txt}

This produces a similar table to the previous example, but with extra columns showing the cluster values extracted from a second file listed after the "-c" flag. The second input file (t statistic in this example) is referred to as "COPE" (see cluster guide).