[FieldTrip] Cluster-based permutation tests on pre-defined time windows

[Stefanie Elisabeth Sturm]

Dear list members,
I have a question regarding cluster-based permutation tests using ft_timelockanalysis (monte-carlo). I am comparing two conditions of time-locked EEG data across 25 subjects and I expected to find differences in certain pre-defined latency ranges, like the N1, P2 and P3 component ranges. When I do a cluster-based tests across the entire epoch, which in my case is defined from -100 to 500 ms relative to stimulus onset, I don’t get any significant clusters. When I reduce the size of the latency range, for example from 0 to 200 ms, I get a significant cluster (which is what I expected based on visual inspection of the ERPs). Now I am unsure what is the right approach. Can you give me any advice?
Thank you!
Stefanie


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