Hi Wang,
you can do different types of analysis. You can do a vertex-wise comparison, in which case you'll have about 150,000 tests/hemisphere. This makes the multiple comparison problem pretty bad, so people frequently collapse into regions of interest (ROIs). We provide anatomical ROIs which you can use for this purpose.
does that clarify things? I don't understand the red-green part of your question.
cheers Bruce
On Sat, 26 Feb 2011, [GBK] Íô¹óºê wrote:
Hi all,
I want to analyse the thickness difference between patients and normals,but I can not understand the results that I got from qdec-analysis .I hope someone can help me.
Firstly,as the papers says, the Cortical (surface-based) Analysis measures the Distance between white and pial surfaces , get One value per vertex in result.And also,there are 33 areas when we choose to analyses,and we can only get the thickness of these 33 areas per hemisphere,so,my question is why it has just one thickness value in such a large area on the hemisphere?
Secondly,in my opinion,there will be red or green in a large scale if it
does exist thickness differences between the patients and normals in one areas,such as "lh_bankssts_thickness",but,the results seems not in that way,why?
Do I explain my questions clearly?
Thanks,
wang