Hello everyone, I am very new to EEG and I am trying the analyse the changes in alpha and beta frequency bands during stress scenarios. I am continuously recording 7 trials each one marked s1-s2-s3.
S1 corresponds to the first event marked in my virtual game: it is a cognitive test and lasts for 50 seconds.
S2 corresponds to when the stressor is triggered. This one is triggered at the second 50 and lasts for 30 seconds.
S3 marks the end of the game.
I keep getting issues on the segment length being out of bounds and I believe this is because when extracting the epochs, I set s1 to range [0 50] however the latencies of other trials go over 50sexonds.
Any idea on how I could fix that?
Thanks a lot in advance
Hello,
As was suggested in the MNE forum, it might be best to extract the epochs with different timing separately from each other, so first S1, than S2 etc. to circumvent the fact that epochs normally have the same timing 
Good luck with extracting.
Kind regards,
Steven
I tried that but I believe I should separate and analyse each trial independently so trial 1 corresponds to the first s1 s2 s3 serie and so on. do i have to extract epochs for that?
Hi @jodebelle
For new users, we recommend following the introduction tutorials to understand how to use Brainstorm.
I keep getting issues on the segment length being out of bounds and I believe this is because when extracting the epochs,
what error are you getting? can you share a screenshot?
I am continuously recording 7 trials each one marked s1-s2-s3.
If I understand what you mean, you need to import 2 events:
- from the raw data, import epochs from S1 with 50s length (+ baseline),
-from the raw data import the epochs from S2 with a length of 30s.
you don't need S3.
I set s1 to range [0 50] however the latencies of other trials go over 50sexonds.
what do you mean bu this?
I think you don't need to have the remain data since you interest is within the 50s.