Re: [Freesurfer] interpretation of vertexwise thickness, area, volume analysis

2012-11-19 Thread Douglas N Greve
On 11/15/2012 05:13 PM, Mahinda Yogarajah wrote: Hi, Thanks for the reply. I am using the new script and I should correct myself in that my significant volume changes do seem to correspond (although they are not completely identical) to areas where there are significant area

Re: [Freesurfer] interpretation of vertexwise thickness, area, volume analysis

2012-11-15 Thread Mahinda Yogarajah
Hi, Thanks for the reply. I am using the new script and I should correct myself in that my significant volume changes do seem to correspond (although they are not completely identical) to areas where there are significant area differences (I see no significant thickness differences between my

[Freesurfer] interpretation of vertexwise thickness, area, volume analysis

2012-11-14 Thread Mahinda Yogarajah
Dear Experts, Given that volume is area x thickness, how would one explain significant reductions in volume in a qdec anaysis comparing patients and controls, but not significant differences in area or thickness in the same regions where volume differences are seen. All analyses use the same

Re: [Freesurfer] interpretation of vertexwise thickness, area, volume analysis

2012-11-14 Thread Douglas N Greve
Did you run qcache after installing the new version of preproc-sess? The new version has a jacobian correction needed to make the area and volume computations meaningful. If you have not installed the patch, you can get it from here: