No digital triggers recorded from neuromag vectorview 306

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1

Hi all,

I am processing several data sets recorded off of a neuromag vectorview 306
channel MEG. Most have events recorded on STI101, but two seem to not have
any data for this channel (see attached .jpg screenshot). Can I use
mne_make_combined_event_file to create a event file, or is the absence of
STI101 indicative of a larger problem with the recordings? As I take a
closer look at one of the good files, it does not look like STI001 and
STI006 are being combined into STI101 (which I think is what
mne_make_combined_event_file does); but I don't know what magic happens in
that process. Any advice is appreciated. Thanks!
-Joseph Frantz
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2

hi Joseph,

if you need to dig into the events on the stim channels (change thresholds
or recombine them) I recommend to load the data with Matlab or Python
and extract the triggers manually.

here is the relevant Python file:

https://github.com/mne-tools/mne-python/blob/master/mne/event.py

HTH
Alex

3

Thanks to all who have replied! Turns out a constant value of 512 is being
added to the values on STI101 in these files. I think I just have to
modify my description files and I am good to go. (Thanks Megan!)
-Joseph Frantz