Re: [Freesurfer] PCA on PET / Thickness in Freesurfer

Hi Doug,

I have pasted the correspondences below. My question is, if I want to identify the PCs in a group for a single modality (PET), how should I run the mri_glmfit? A single group design with A contrast of 1 0 (for a nuisance covariate)?

Thanks !

Elijah

Doug:

For within modality, you can add --pca to mri_glmfit (run it with --help to get more info). We do not have ICA tools in FS.

On 12/01/2016 02:04 PM, Foo Keat Mak wrote:

Hi Freesurfer Team,

For a given group, I want to look at the covariance patterns between thickness and PET. Within Freesurfer, what are some general workflow tips on how I could go about performing PCA (within modality) or joint ICA analyses looking at the covariance patterns across modalities? Is the -pca flag a good starting point?

Any feedback is appreciated!

Thanks a lot.

Best Wishes, Elijah

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On 1 Dec 2016, at 23:30, Foo Keat Mak <fkm24@medschl.cam.ac.ukmailto:fkm24@medschl.cam.ac.uk> wrote:

Thanks Doug. Does that mean that a one group design? With a contrast of 1 0 (adjusting for one variable)?