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Problem with triggers

Posted: Wed Apr 18, 2012 3:05 pm
by AlBarca
Hi there,

I am having problems with my triggers. I used E-Prime for my experiment and had triggers such as 101, 202, etc. When I ran the experiment, all the triggers and sentence numbers appeared properly. However, now that I look at the data the triggers appear as S1, S2, up to S8. So for each sentence instead of having, for example, S12 (sentence number) 101 (trigger), I get S1, S1, S1, S1, S1, S7, S1, S1 (in this case I found out S1 represents each word of the sentence and S7 the trigger). I tried to find a coherent pattern that I could use but there does not seem to have any.

Any suggestion?

Thanks,
Alice

Posted: Wed Apr 18, 2012 7:52 pm
by Coen
8-bit unsigned numbers versus binary codes. Use better software to read the files, or limit your trigger codes to 16 (only one line high per code).

Best regards, Coen

Re: Problem with triggers

Posted: Tue May 22, 2012 6:00 pm
by AlBarca
Dear Coen,

Thanks very much for your reply. I now have to use Brain Vision (as opposed to EEGLab before) to analyse my data collected with Biosemi. I converted the data into EDF files but is there a way I could solve this 8-bit unsigned numbers versus binary codes issue so that I could see the right triggers?

Thanks,
Alice

Re: Problem with triggers

Posted: Tue May 22, 2012 6:10 pm
by Coen
The issue won't be solved so long as you use BrainVisison.

Best regards, Coen (BioSemi)