Hi Rick,
You mentioned that I "Currently you have 150s of rest, distributed in 3s
multiples (so 0 or 3 or 6, etc). Is that really how
you want it? Would you prefer a range, maybe 2..10,
say? It looks like the mean ISI should be about 5s,
the way you have set it up. "
For my experiment, I do not have true rest. Instead, I have an baseline 'task' that takes 3-sec to complete. Based on our earlier conversations, I have been coding this as a separate task and not as rest. Thus, I cannot have the baseline 'task' range from 2..10 sec because then people would have too little time (2 sec) or too much time (anything > 3 sec) to do the task.
I am having trouble figuring out what the mean ISI would be because the metrics that are outputted are not setup to have no real 'rest'.
QUESTION: How did you arrive at the ~5sec ISI?
Also, I am noticing another artefact of coding the baseline task as a condition. The best randomization had the baseline condition occurring as the first stimulus in one of the runs. In my case, the baseline condition should create the jitter between my conditions of interest and should not occur at the beginning or end of a run. Note that I already have 12 sec of the baseline task to begin each run (to reach steady state) and 9 sec at the end to catch the end of the HRF. I want the first stimulus in each block to be a condition of interest (labels 1-8), not the baseline condition.
QUESTION: Is there any way to prevent the baseline 'condition' from occurring first or last in a run?
Regards,
Christine