coherence stats

Bernhard Staresina bps231 at NYU.EDU
Wed May 21 02:58:14 CEST 2008


Dear FieldTrip experts,

I have a quick question about the statistical assessment of coherence. I
first derive coherence values across two channels of interest for condition
A and condition B by running (i) FREQ = freqanalysis [with cfg.output =
'powandcsd'] followed by (ii) COH = freqdescriptives(FREQ), separately for
each condition.
Now, how can I assess whether the coherence values differ significantly
between condition A and condition B? First I thought the I can just plug in
COH_condition_A and COH_condition_B into freqstatistics (using montecarlo
randomizations). But given that COH doesn't contain trial-by-trial data any
more, that doesn't seem to work. So, I assume that I should use
FREQ_condition_A and FREQ_condition_B instead? But if so, how does the code
know what data to choose for the stats (e.g., crsspctrm versus powspctrm)?

Any guidance would be appreciated.

Best,
Bernhard


----------------------------------
The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.



More information about the fieldtrip mailing list