[FieldTrip] Channels to be highlighted after a cluster-based permutation test

Jaime Ibánez Pereda jaimegus at gmail.com
Mon Jun 3 17:51:04 CEST 2019


Hello everyone,

I am currently running a cluster-based permutation test on my TMS-EEG data
and I saw something in the fieldtrip tutorial that I'm not sure how to
interpret: according to the lines of code on the fieldtrip's website (
http://www.fieldtriptoolbox.org/tutorial/cluster_permutation_timelock/), to
decide which channels are to be highlighted in your topoplots aimed to
characterize the region of a significant cluster you can use the 'all'
command, thus implying that you consider a channel pertaining to the
significant cluster if it is always active during the whole time window
that you are looking at. Would anyone please let me know why 'all' is being
used in this case instead of some alternative line of code simply
highlighting channels that are part of the cluster and significantly
changing at any given time during the analyzed interval?

I other words, in the referred link, the following code is used (e.g., in
the "Within-subjects experiments" example, when the scalp maps are plotted):

*   pos_int(i1) = all(pos(i2, m(k):m(k+1)), 2);*

However, in this case, I would have thought that something like this would
be more appropriate:
  * pos_int(i1) = sum(pos(i2, m(k):m(k+1)), 2)>0;*

I wonder whether previous articles published using these tools have used
the 'all' command to establish the channels considered to be part in a
certain cluster?

Thanks in advance,
Jaime
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20190603/2254bb7f/attachment-0001.html>
-------------- next part --------------
_______________________________________________
fieldtrip mailing list
https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
https://doi.org/10.1371/journal.pcbi.1002202


More information about the fieldtrip mailing list