clustering after sensor picking?

[Walther, Alexander]

Dear list,

I am facing a question regarding the MCP in time-frequency-analysis. In
order to boost the effect size, I picked several ROIs on the MEG scalp
by running a Task-versus-Basline Comparison (values averaged over all
subjects, all conditions, timepoints and frequencies) and selecting the
highest raw effect patches. Since FDR-correction seems to be too
conservative and yields no results in following analyses, I tried the
cluster-method which works pretty well. Is it (statistically) correct to
apply clustering after sensor picking? Since its test statistic refers
to the clustering of /adjacent/ sensor-pairs of the whole spatiotemporal
grid (which does not exist any more after the selection of ROIs), I
wonder whether it is still appropriate. Any advice would be helpful.

Merry xmas in advance!


Best

Alex

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