Trigger in OpenSesame firing too early
Hey there,
I am currently programming an eeg-study using OpenSesame. In the study, I am showing my subjects a sequence of words per trial. Each word has a fixed amout of time it is being shown, before the next word of the sequence is presented. Now between specific words in the same position in each trial I want to send a trigger (let's say for instance in the third word of each trial). This happens for multiple words in the sequence. In my logfile the time between two fired triggers does not sum up to the time the words between the triggers are supposed to be shown. So if I fire Trigger A, then show Word 1 for 400ms, then Trigger B and then Word 2 for 400ms. But the time between trigger A and B in my logfile is just 251ms (not always this value, it varies). Does someone know how to solve this problem?
Thanks in advance! :)
Comments
Hi @SushiSushi ,
Could you upload the experiment script here, or an example of how you implement this? Without seeing the actual experiment it's a bit difficult to tell where this problem might come from.
Cheers!
Sebastiaan
Check out SigmundAI.eu for our OpenSesame AI assistant!
Hi Sebastiaan,
thanks for your help. A short extract of the script is enclosed in a .txt file I attached to this message. It shows an example of how a loop is structured in my study. In every trial words like nouns, verbs or adjectives are shown for 550 ms and specific functional words like prepositions and definite articles will only be shown for 400 ms.
Does this help you or would it be more helpful to provide the complete script? I have to warn though, the complete script has (due to the large number of trials) multiple thousands of lines. Additionally I included the trigger log file so you can see, that the triggers do not fire when they are supposed to.
Thanks in advance!
Oh, I forgot to tag you (@sebastiaan) on this one.
Hi @SushiSushi ,
The script excerpt doesn't contain any code related to sending triggers 😉 So yes, please provide the full experiment or at least a working example (i.e. something that I can open in OpenSesame) that illustrates the issue.
Cheers!
Sebastiaan
Check out SigmundAI.eu for our OpenSesame AI assistant!
Thanks a lot for your help! I was able to solve the problem on my own after carefully looking at everything. Turns out the triggers were fired correctly after all, I was just looking at the wrong numbers when I was looking at the log file.