Dear all,
I used gppi within an event related design to show connectivity differences between patients & controls. A reviewer is concerned that differences in low frequency fluctuations between the groups might confound the analysis of task-based connectivity. Although I cannot definetly exclude an influence, from my perspective the ppi approach within an event related design with stimulus durations >3 seconds should be rather robust against low-frequency modulations that take place on a different time level. Is this assumption right?
Best & thanks in advance
Ben
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