[open] sending multiple triggers to an EEG machine

elenaNU

Hi,

I am new to this software and I apologize in advance if I should have posted this somewhere else.
I have an experiment where I present auditory stimuli (sentences) to participants undergoing EEG, and I need to send triggers in the middle of the audiofile (multiple triggers for each sentence, at different onsets for each sentence).
I downloaded the parallel port trigger and was able to communicate with the EEG recording system (I have a Brain Vision system) through the parallel port, adn I was able to send triggers at the onset of each sentence.

However, I am not sure how can I send multiple triggers within the sentence.

Can somebody help me?

Thanks in advance,
Elena

eduard

Hi Elena,

Welcome to the Forum!

If you set the duration of your audiofile to "0", the experiment will proceed with the next items in the sequence, while the audiofile is playing.
Now you can put as many parallel port trigger items in the sequenceas you want send triggers. In order to to send them at exactly the timepoint as you wish, you can use the advanced delay, or an inline_script, where you can specify the time you want to wait by using self.sleep(time).
Keep in my mind that the triggers have to be reset to 0, after you send a trigger. If the trigger duration is bigger than "0", it will be done automatically. If it is "0", you have to include set it back to "0" yourself (simply sending another trigger with the value "0").

Good luck,
Eduard

elenaNU

Thanks for your quick reply.
I tried as you said but it does not work...
Reading through the forum it seems that I need to use an inline script and use another plugin, the DLportIO.
I downloaded the plugin and installed it, and then tried to follow the instructions from a previous thread on the forum.
However, there is one main question: it is not clear to me how to use the 'self' function, as I tried to use the self.get and self.sleep commands but they do not work.
Is is something I need to define in the "prepare" phase?
If so, how do I do that?

Thanks,
Elena

eduard

Hi Elena,

I don't know whether this is the issue, but you should be careful to what you refer, if you use self.
If you use self._functions in an inline_script, self refers to the inline_script-object. If you want to refer to the experiment-object, you have to use self.experiment._function or simply exp._function_.

In general, it shouldn't matter whether you put it into the run or prepare phase (as long as items that follow later in the sequence do not depend on stuff you define in the inline_script.

Eduard