Hello again,

I would like to ask one last thing.

How can the class averages computed from csdbase.y.ocn.dat not match the gamma.mgh values in the cluster?

e.g. How can gamma show +29 in a vertex that is part of the significantly positive cluster in an A-B contrast, while the average of all values taken from csdbase.y.ocn.dat referring to class A in that same cluster is lower than that of class B (average of values of input y for class A = 20.367; average for class B = 20.401)?

Are the values in csdbase.y.ocn.dat not corrected by the variables chosen as covariates?

Thanks again!

Antonio Bonifanti

Il giorno mer 15 feb 2023 alle ore 18:36 Antonio #30 <toni.bonif2511@gmail.com> ha scritto:

Hi,

1. I was wondering why the --fsvol argument in -pctsurfcon takes rawavg.mgz by default, when most literature on grey/white contrast tends to compute it from nu.mgz.
Is the intensity-corrected volume to be preferred in all cases or was there a reason for choosing rawavg as a default while writing the script?

2. I would also like to ask whether or not you believe the values of smoothing kernels seen in literature for grey-white contrast (which often are over 20mm) to be adequate for such a measure.

3. As a final note, would you say it is appropriate, from a statistical standpoint, to compare the results of group analyses conducted on the two hemispheres with different covariates? (e.g. with mean left cortical thickness and mean right cortical thickness rather than mean whole cortical thickness)

Thank you for your time!

Antonio Bonifanti