Dear FSL Experts,
I'm attempting to analyze fMRI data collected from a prospective intervention study consisted of an experimental group and control group. Both groups were scanned at baseline and 12-months (post-intervention). During the scanning sessions, two tasks were performed:
1. Block-design finger tapping task.
2. Event-related design cognitive task.
What I'm interested in finding is to determine if there are differences in changes in functional connectivity/network over the 12 months between groups.
Pleas correct me or point me to the right direction if my following rationale is wrong: I came up with two potential ways to perform the analysis for the block-design finger tapping task:
1. I would first input only the baseline functional data into MELODIC - TICA; then I would do the same for the 12-months functional data and end up with two Melodic_IC.nii.gz files that contains the group components (one for baseline and one for 12-months). Subsequently, I can use fslmaths -sub with these two files to calculate the difference between scanning sessions (12-months minus baseline). Then use the output file from fslmaths as the input for Dual Regression to find group differences.
or,
2. I would select both baseline and 12-months as inputs into MELODIC-TICA, then define the contrasts in the GLM that will be later inserted into Dual Regression, for example:
Experimental_baseline Experimental_12M Control_baseline Control_12M
C1 -1 1 0 0
C2 0 0 -1 1
C3 1 -1 0 0
C4 0 0 1 -1
C5 1 0 -1 0
C6 0 1 0 -1
Where C1-C4 determine differences within group over time; C5 and C6 determine differences between group within the same scanning session.
Next, for the event-related design task, I will apply either one of the above rationale to perform MELODIC - Multi-session Temporal Concatenation, and in the GLM setup I will load the text files containing stimulus onset information?
I apologize for the lengthy question but I would really appreciate any insight or advice on how to approach this analysis,
Thanks in advance!
Liang
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