Hi Bruce,

Thanks for your reply. This makes sense. One remaining question is which surface is used to compute the eigen-axis, is it the white surface?

Best,

Martin

On 02/03/14 15:27, Bruce Fischl wrote:

Hi Christian and Martin

mris_divide_parcellation finds the primary eigen-axis of the parcellation along the cortical surface, then splits it up into as many units as specified (either enough to get it under the area threshold, or explicitly specifed in a split file)

cheers Bruce

p.s. the code is open source so you are always welcome to grab it and take a look

On Mon, 3 Feb 2014, Martin Luessi wrote:

...

I'm wondering about this as well. It would be great if someone who is familiar with the FreeSurfer code could explain the split algorithm.

Best,

Martin

On 01/29/14 14:36, Christian Brodbeck wrote:

...

Dear Freesurfer developers,

I am trying to replicate mris_divide_parcellation for mne-python (https://github.com/mne-tools/mne-python/pull/1085). I think I am doing the same as the MRISdivideAnnotationUnit function (https://github.com/neurodebian/freesurfer/blob/master/utils/annotation.c#L47...), but the result still looks different. Could someone point out how exactly the split is done, and if there are any steps in addition to the function? Are there any measures that are taken when the split would result in two disconnected regions belonging to the same label? And what surface is the split performed on (I would assume that would be “white”)?

Thank you!

Christian _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

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Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

Thanks a lot Bruce! Using the sphere surface was what I was missing.

Christian

On Feb 4, 2014, at 12:16, Bruce Fischl fischl@nmr.mgh.harvard.edu wrote:

it's the ?h.sphere so that folding isn't an issue On Tue, 4 Feb 2014, Martin Luessi wrote:

...

Hi Bruce,

Thanks for your reply. This makes sense. One remaining question is which surface is used to compute the eigen-axis, is it the white surface?

Best,

Martin

On 02/03/14 15:27, Bruce Fischl wrote:

...

Hi Christian and Martin

mris_divide_parcellation finds the primary eigen-axis of the parcellation along the cortical surface, then splits it up into as many units as specified (either enough to get it under the area threshold, or explicitly specifed in a split file)

cheers Bruce

p.s. the code is open source so you are always welcome to grab it and take a look

On Mon, 3 Feb 2014, Martin Luessi wrote:

...

I'm wondering about this as well. It would be great if someone who is familiar with the FreeSurfer code could explain the split algorithm.

Best,

Martin

On 01/29/14 14:36, Christian Brodbeck wrote:

...

Dear Freesurfer developers,

I am trying to replicate mris_divide_parcellation for mne-python (https://github.com/mne-tools/mne-python/pull/1085). I think I am doing the same as the MRISdivideAnnotationUnit function (https://github.com/neurodebian/freesurfer/blob/master/utils/annotation.c#L47...), but the result still looks different. Could someone point out how exactly the split is done, and if there are any steps in addition to the function? Are there any measures that are taken when the split would result in two disconnected regions belonging to the same label? And what surface is the split performed on (I would assume that would be “white”)?

Thank you!

Christian _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

---

Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

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