You should synchronize the computer that has the E-Prime installed on it with the Computer that acquires and stores the EEG signal. Usually this is done by an internal clock. Can you give more information on the software that you use for acquiring the EEG data? Is it NetStation for example?

Hi,

I use Brain Recorder for acquiring EEG data. My problem is: I already have my recordings but one type of marker is missing for some participants.

So I have to include these new markers afterwards.

Thank you for your answer.

Hey Joy,

U can put the missing marker on the the basis of ur stimulus time and sampling rate.

Well if you stored in the E-prime result file for each subject all the sequence of your experiment (condition number, response type and timing parameters associated with each of them trial by trial) then it won't be difficult to make a little program (a matlab script for example) that modifies the BrainVision marker file. I have had the same problem and I have solved in that way.

Dear Amit and Valia,

I finally solved my problem, easy when you modify the BrainVision marker file indeed.

Thank you anyway for your answers!

For multiple computer application i recommand using a millisecond precise device such as this one https://www.braintrends.it/devices.html.