To whom it may concern,
First of all I should thank Benjamin Kay for his previous answers. I would be thankful if somebody who is expert with melodic or work in Analysis Group, FMRIB could answers my question.
I want to do group-ICA analysis for my data more than one time. Therefore, I decided to use images resulted from pre-processing and registration of the first running of the concat-ICA as input for the next analyses.
So I did the following method for the next analyses:
Choosing the images from " reg_standard" folder of each subject (from my first completed analysis) and disabling all of "Pre-Stats" icons. However, since Melodic doesn't let us skip from "Registration state" I just chose 3DOF (for increasing speed) in the registration of Atlas .
In other words, I tried different situations in which Set A is initial Data and Set B is Data after pre-processing and registration.
First situation:
Set A ->(Pre_Stats and Registration) -> Set B -> dimensionality estimation. and ICA analysis
Second situation:
Set B -> dimensionality estimation and ICA analysis.
But the results are strange.
Although it is reasonable to have a difference between each time you run ICA analysis, the difference between when I do the whole process (I have done that twice) and when I use the registered_filtered_images and skip the pre-processing (I have done that 3 times) is too much. For instance, in the first situation I have 48 components in both tries but for the second situation there are 68 component for all of 3 times.
Would you please explain what my problem is.
Thank you in advance,
Best regards,
Armin
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