External Email - Use Caution        

Hi Julien

In researching this a few years ago I asked the question

What exactly has been
>> done to change the .label
>> (e.g. lh BA44.label) to
>> .thresh.label (e.g. lh
>> BA44.thresh.label?

And was told

The .thresh labels have been
>> thresholded with a p-value
>>   threshold that is "best" on our
>> training set of
>>   manually/architectonically defined
>> labels.

I then looked into this a bit further and found the following explanation:

On 14-09-08 12:39 PM, Anastasia Yendiki wrote:
> On the difference between .thresh and "not .thresh" labels: The
> BA labels come from averaging histologically derived labels from a set of
> post mortem brains. The non-thresholded version is just the sum of the
> corresponding labels from the different brains in fsaverage space. So
> vertices are included even if only one of the brains had their BA in that
> vertex, which means that these labels are going to be rather large. In the
> thresholded version, a threshold has been applied to the average BA label,
> to make it have an area as close as possible to the average area of the
> individual BA labels. I hope this makes sense.


I hope this helps!

Trisanna Sprung-Much
Research Associate
McGill University
MD Anderson Cancer Centre
-- 
 

On 2021-02-18, 3:27 AM, "[email protected] on behalf of 
julienbesle" <[email protected] on behalf of 
[email protected]> wrote:

            External Email - Use Caution        
    
    Hello,
    
    The ex-vivo BA label and annotation files named 
    ?h.BA??_exvivo.thresh.label and BA_exvivo.thresh.annot seem to be 
    thresholded versions of the corresponding probabilistic BA labels. Was a 
    simple threshold on the probability used and if yes, what was the value?
    
    In addition the annotation files, whether thresholded or not, only have 
    one label per vertex. Are the labels based on the maximum probability 
    across all BA labels?
    
    Thanks
    
    Julien
    
    -- 
    ------------------------------------------------------
    Julien Besle
    Assistant Professor
    Department of Psychology
    Faculty of Arts and Sciences
    American University of Beirut
    Riad El-Solh / Beirut 1107 2020
    Lebanon
    
    Jesup Hall, Room 103E
    Tel: +961 1 350 000 ext. 4927
    -----------------------------------------------------
    
    
    _______________________________________________
    Freesurfer mailing list
    [email protected]
    
https://secure-web.cisco.com/1XQKd9pXAr8qUGqeGMndR3TJOl3i07YuFeBt8v6LPq0Ro62i6h-ivXgLE85MdCQy_C9CD3rVltO97GONz3BNW3rblKwSS2Ve88Pc8LZmlHrJKU2H0Bxx4KA2gZDrgSrpyTJ6rKDfwa1Ooqb8k_mekLQN8Jy2TO8jA7BLe4YkwwoliTBMfhn5k3YGSkpwixody3rFZvZ8vp1QZwZItV_nZFkSrO7aSNXgJwgfDnsRBin97WVFydnfBO3ZYqsWiVTpmAkPZaY-ypSATaVJPP7NZmw/https%3A%2F%2Fmail.nmr.mgh.harvard.edu%2Fmailman%2Flistinfo%2Ffreesurfer
    


_______________________________________________
Freesurfer mailing list
[email protected]
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

Reply via email to