Word-by-word presentation with EEG triggers
This is likely a very basic question but I can't for some reason wrap my head around it. I will be running my first EEG experiment soon (E-Prime 3.0 + BioSemi) and need to send codes to the trigger interface when the target word is displayed. It will have a word by word presentation. However, I am not sure how to do that because all my sentences have a different number of words in them. If I split my sentences into different columns in my source file, the target words would not be in the same column. Has anyone dealt with the same problem?
I might misunderstand you. Can’t you just use a second column with a flag value (e.g, 1 and 0) that indicates if the value in the sentence-column contains the trigger word? Or, if you have several trigger words but each sentence can contain only one of them you could add a trigger-word column that will hold the value of the trigger word that is included in the value in the sentence column.
I hope, it helps.
Hi Phillip, thanks for your reply! Maybe I explained it poorly.
Every sentence contains a target word (it's the last word in every sentence).
I am not sure how to achieve a word-by-word presentation with just one "sentence column". I thought you must have one word per column and then multiple stimulus objects each displaying different columns in your source file.
How I understand it, I can use task events to send a timestamp to the trigger interface when the target word is displayed. But I don't know how to do that when each sentence has a different number of words in it, hence different number of columns? I am just very confused.
When I programmed experiments before, I would just split sentences into an equal number of parts (say, "beginning", "pre-target", "target", "post-target", etc.) because it didn't have to be exactly one word on the screen at a time. Now it has to, and I am lost.
Please sign in to leave a comment.