I need your help to use SuperLab 4, my english is not very good, I’ll try to be as clear as possible!
I have a block linked to several trials. Each one of these trials is linked to an event, but only 2 of these events are stimuli lists. How would it be possible to have only one event in each stimuli list, picked randomly, every time the block is presented?
If I select “Randomize the events in this trial”, all the stimuli from the list are presented before getting to the next trial. Is it possible to randomize the items of a stimuli list but to pick them only one at a time?
In other words, this is what I would like to get:
(B=Block, T=Trial, E=Event)
B1 - T1 - E1
B1 - T2 - One of E2, picked randomly (E2 being a stimuli list)
B1 - T3 - E3
B1 - T1 - E1
B1 - T2 - Another one of E2, picked randomly
B1 - T2 - E3
…
And so on, until every stimuli of the E2 stimuli list have been presented.
For the vast majority of cases, you do NOT want to randomize the events in a trial. In your case, it would do nothing.
Your experiment should be set up like this:
B1 - T1 - E1
B1 - T1 - E2 – which is linked to a stimulus list
B1 - T1 - E3
Set B1 to randomize trials in the block.
That’s all.
What happens at runtime is that any trial containing an event that uses a stimulus list will have copies created–one for each item in the stimulus list. In effect, the trial you see is a template. You can see the result of this process by selecting “Expand Events That Use Lists…” from the “Experiment” menu. This will open a copy of your experiment representing what will happen at runtime. When you’ve seen enough, close the copy to get back to your original experiment.
Thank you!
It seems much more simple than what I thought … :o
One more (and hopefully last) question:
I put stimuli in a random order and of course I would like to save the order in which they are presented for each participant. As the participants don’t have to give a response to these stimuli, these stimuli don’t appear in the collected data file. How is it possible to save them, even though no answer is required?
Isn’t it the case that there will be a line in the logfile with a “NR” reponse for an event that only uses a time limit to end it, as long as “record and save response” is checked?
Unfortunately it isn’t… There is no trace of the stimuli that have no answer required, even if the “record and save response” is checked… it surprises me also!
Quote: "One trick is to give the event a time limit of 1 millisecond. "
The problem is that the stimuli are audio files from a stimuli list. They don’t have all the same duration and the program should wait until the sound has finished playing before moving to the next event. So it is not possible to give a fixed time limit to them…
Do you have another trick in mind?
Thank you!!
If the program should wait until the sound has finished playing before moving to the next event, then the 1 millisecond trick should work in your case because the 1 millisecond is appended at the end after the sound is done. It would have been a problem the other way around, i.e. if the Wait for audio to finish playing was NOT checked.
