Hi, I use sparse-acquisition for speech collection.
The experiment stimuli (using Presentation software) are presented as follows:
1. subject see a <-> sign, 2800ms
2. subject see a <word>, 2000ms
3.subject see a <-> sign, varies
4. subject see a <plus> sign, and say the word he saw previously, 2000ms
5. subject see a <-> sign, pulse scan occurs here
This 5 steps are 10 sec.
TR is 2.5sec.
Under the Specify 1st level-Condition- onset time, I wonder which onset time should I input? Is it the onset time of the 1st step when subject saw the first <-> sign? My colleague said that I should start the onset time at the step 2. where subject see the <word>, because it will take about 5 sec to reach the hemodynamic peak. But, I am not very sure.
Should I put the time output from the presentation software logfile? I appreciate your advise.
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