Dear John
Thanks for your answer. I have some further question and wish you give me some advise.
1. Using SPM12b longitudinal toolbox for 3 time-point registration. I have a question about how to setup the option of "time". In order to calculate GM tissue volume of each time-point, I think I need to setup this option with identical value (use 0,0,0). Is it right to set 0,0,0 for this three time-points data or i should set the real time interval for this option?
Specify the times of the scans in years. If there is a one year interval between scans, then specify 0, 1, 2. \you
would only enter 0,0,0 if all scans were acquired simultaneously.
I will use the real scan time which you mentioned above for this option. If I use the real scan time for this option, the output of step5 whether indicated the absolute GM tissue volume for the corresponded time-point ? Because I want to use these GM tissue volume data of each time-point to construct the mixed effect ANOVA model to test where the time 2 volume is smaller than time 1 volume in specific group, do I need to adjust the time interval between scan time of each participants in this setting ?
(Step 5: Dartel's normalise to MNI space using the output from (3) with "tissue modulation" option. The output of this step is the GM tissue volume of corresponded time-point.)
Best
Paul
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