Hi there,
we completed 1st level analyses of a fMRI activation study and also applied randomise tfce on the resulting 1st level copes. Inspired by the technical report on TFCE and some suggestions on the mailing list, we trialled several parameter combinations of tfce height and extent. We are aware of the recommendations (H=2 E=0.5) and the discouragement to change these settings, but may I ask if corrected for multiple comparisions, the results would be valid? So far we seem to get the best results at the lower end of H end E, that means, I assume, that the input signal is not much enhanced at all (H=0.1 E=0.1, see figure 10 in technical report)? Likewise, we are using cope images not raw tstat or zstat images, so has anyone made experience with suitable values?
Thanks very much in advance,
Torsten
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