[Freesurfer] mri_glmfit error: negative DOF -10

Hello, I am using mri_glmfit to perform a correlation analysis between some surface-based DTI measures and a behavioural outcome (grip), aiming to correct for scannertyp (C,I,W), handedness (R,L) as discrete variables and age (AGE) and duration (Mo) as continuous covariates. Please find the fsg

[Freesurfer] mri_vol2surf projection of white matter results

Dear Freesurfers, I transferred the white matter binary mask (derived from aseg, volume) to FSL and performed probabilistic tractography in it. Now I'd like to project the 'outer' white matter results (vol) onto the white surface. To test for the acuracy of this approach, I tried to project

[Freesurfer] mri_vol2surf projection of white matter results

Dear Freesurfers, I transferred the white matter binary mask (derived from aseg, volume) to FSL and performed probabilistic tractography in it. Now I'd like to project the 'outer' white matter results (vol) onto the white surface. To test for the acuracy of this approach, I tried to project

[Freesurfer] how to threshold mgh surface and save the file

Hi, I'd like to theshold a surface mgh file at a certain value, set all values below the threshold 0 and save the file for further statistical analysis. mri_binarize creates a binary mask which does not help in my case. Could anybody help me with the apprpriate command? Thank you very much

[Freesurfer] help needed with fsgd file and contrast matrix for correlation analysis

Dear all, I have 2 short questions regarding a correlation analysis I'd like to perform with mri_glmfit (surface-based DTI data are correctly preprocessed and concatenated into mgh file, statistics are performed on fsaverage space). 1) I'd like to look for correlation between the surface-data

[Freesurfer] help needed with fsgd file and contrast matrix for correlation analysis

Dear all, I have 2 short questions regarding a correlation analysis I'd like to perform with mri_glmfit (surface-based DTI data are correctly preprocessed and concatenated into mgh file, statistics are performed on fsaverage space). 1) I'd like to look for correlation between the surface-data

Re: [Freesurfer] combination of different surfaces across the group for mri_glmfit statistics

Dear Douglas, thank you for your reply. > Hi, > I have two questions: > 1. > I have created specific surfaces in fsaverage rh for each of my 20 > subjects. (xy.mgh) > I'd like to run statistical analysis within the common surface area > which is included in all subjects. > Therefore I wonder how

[Freesurfer] combination of different surfaces across the group for mri_glmfit statistics

Hi, I have two questions: 1. I have created specific surfaces in fsaverage rh for each of my 20 subjects. (xy.mgh) I'd like to run statistical analysis within the common surface area which is included in all subjects. Therefore I wonder how to combine those surfaces. My idea would be to add

[Freesurfer] GLM | group comparison and correlation on surface with whole-brain DTI/tractography results | How to setup fsgd and contrast matrix?

Hi Freesurfers, I managed to project tractography results (seed-based whole-brain tractography performed in FSL) onto the surface of each individual subject (19 OLD, 19 YOUNG). Each individual surface (including the results) has been transferred to fsaverage to allow statistical group compari