How to add fillers to an experiment?

I am using PsychoPy Builder to build a cross-modal antecedent priming experiment. Everything goes well without the fillers, but a problem occurred when I was trying to add the fillers.

In my design, there are 36 experimental trials and 64 fillers, which need to be presented in a pseudo-randomized way that no more than 3 experimental trials appear consecutively. The procedures of experimental trials and fillers are exactly the same, so I thought I could use the same routines for them. I made the flow like this:

The loop types of “Fillers” and “trials” were both set random. When I ran the experiment, fillers just appear all together, before experimental trials. Is it possible to pseudo-randomize the order.

I am not very familiar with coding. If this problem must be solved by coding, could you please let me know where to add the code component or where in the script to insert the code? Thank you!

What is the actual difference between a filler and experimental trial?

Hi Michael,
I have a similar problem.
I am designing a go-nogo task. I’m drawing my conditions from a. Csv file. Initially I was presenting the trials (say 40) in random order so it wasn’t a problem. But now I want to change the design so that a no go trial is followed by a go trial always while keeping the overall randomisation. How could I possibly achieve this pseudorandomisation in Builder?

The difference between my go and no go trials is that for go trials, I have set the duration of the nogo signal to zero. Thus stop duration being the variable value being drawn from csv file for different conditions

Thank you in advance forfor any insight.