First,now I want to add four parts of the occipital lobe's gray matter volume(Lateral Occipital,Lingual,Cuneus,Pericalcarine) to evaluate occipital lobe development,can I do like this?

   second, I also want to use the occipital lobe's cortical thickness to evaluate development,but four parts of the occipital's cortical thickness is different,so I add the four parts of the cortical thickness and divide 4,after that I get the average value,then use this average value to do  statistics analysis,can I also do like this?

Thank you very much!

hankee