Dear SPM users,

 

I am trying to run a PPI analysis using the gPPI toolbox. I can build a design matrix, but the script fails at estimation. When I try to manually estimate the SPM.mat via the SPM gui, it seems to work. I suppose something is going wrong in “spm_estimate_ppi.m” but I cannot figure out where and why.

 

Below the parameter file (P) and the failure message I am getting.

 

Any help would be appreciated,

 

Sincerely Froukje de Vries

-----------------------------------------------------------------------------------------

 

P =

 

            subject: '31_101'

          directory: 'F:\fMRI\analyses\1stlevel\map_10\31_101'

                VOI: 'F:\fMRI\analyses\PPI\ROI_building\6mm_ROIs\6mm_R_DLPFC_39_38_28_masked.nii'

             Region: 'gPPI_test'

           Estimate: 1

           contrast: 5

            extract: 'eig'

              Tasks: {'1'  'N0'  'N1'  'N2'  'N3'}   % the same thing happens when it is set to ‘0’ ‘N0’ etc %

            Weights: []

            maskdir: []

           equalroi: 1

             FLmask: 0

               VOI2: {}

           analysis: 'psy'

             method: 'cond'

      CompContrasts: 1

           Weighted: 0

          Contrasts: [1x1 struct]

 

 

estimate_PPI.m

 

SPM8: spm_spm_WB (v4515)                           11:14:42 - 21/08/2013

========================================================================

IPlanes   1-46 /46                       :                              ...done

Temporal non-sphericity (over voxels)   :             ...ReML estimation

  ReML Block 1               

  ReML Iteration 1                      :        ...4.075825e+001 [+4.25]

  ReML Iteration 2                      :        ...1.349581e-001 [+4.50]

  ReML Iteration 3                      :        ...2.315530e-003 [+4.75]

Estimation Failed

Warning: Missing conditions!!! Invalid Contrast

Invalid Contrast

PPI Contrasts were not estimated for some reason.

 

ans =

 

        xY: [1x1 struct]

       xBF: [1x1 struct]

     nscan: 336

      Sess: [1x1 struct]

       xGX: [1x1 struct]

        xX: [1x1 struct]

       xVi: [1x1 struct]

     SPMid: 'SPM8: spm_spm (v3960)'

        xM: [1x1 struct]

     xsDes: [1x1 struct]

       swd: 'F:\fMRI\analyses\1stlevel\map_10\31_101'

      xVol: [1x1 struct]

     Vbeta: [1x5 struct]

    VResMS: [1x1 struct]

        VM: [1x1 struct]

      xCon: [1x19 struct]

 

Froukje de Vries, MD

PhD student

 

Department of Psychiatry

VU university, Medical Faculty, Room C461

Van der Boechorststraat 7

1007 MB, Netherlands

phone: 020-4449635

email: [log in to unmask]

monday-thursday