Sources statistical file with only clusters above certain threshold

4

You can get the indices of the vertices of a ROI in the structure of the cortex surface:
https://neuroimage.usc.edu/brainstorm/Tutorials/Scouts#On_the_hard_drive

And then compute the max t or min p over these vertices.
Example from the introduction tutorials:

>> SurfaceMat.Atlas(1)

ans = 

  struct with fields:

      Name: 'User scouts'
    Scouts: [1×2 struct]

>> SurfaceMat.Atlas(1).Scouts(1)

ans = 

  struct with fields:

    Vertices: [2854 2897 3000 3001 3002 3003 3085 3087 3089 3137 3187 3223 3254 3376 3500 3501 3543 6849 7168 7211 7263 7335 7482]
        Seed: 3223
       Color: [0 0.8000 0]
       Label: 'A1L'
    Function: 'Mean'
      Region: 'LT'
     Handles: []

>> min(StatMat.pmap(SurfaceMat.Atlas(1).Scouts(1).Vertices,:), [], 1)

ans =

  Columns 1 through 19

    0.4338    0.0115    0.0918    0.6028    0.3336    0.2267    0.3208    0.4791    0.0246    0.1973    0.2029    0.0395    0.1011    0.1080    0.1304    0.3518    0.6908    0.0330    0.0549

...