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Counterbalancing based on keys

I have been trying to counterbalance the practice conditions to the experimental ones and for some reason, my logic seems to not match with the one used in PsychoPy.

So, I have a practice block (including a practice trial) where the subjects have to use either Group A or Group B of response keys. I’ve set this block as sequential. In order to pass to the next block, the Experimental One, they should achieve 80% in the practice trial (already programmed). Considering they achieved 80% in the trial, they have to move on to the experimental block, in the experimental block there are two groups of trials, one group of trials that matches Group A’s keys and one group of trials that matches Group B’s keys. Is there any way to programme participants to see the right group of trials based on what they saw in the Practice Block? For instance, when in practice block they have to use Group’s A keys, they should have to use Group’s A keys in the experimental condition too. I’ve tried numerous ways to do so, but none of them worked.

How do you specify what keys to use in the Practice block? Presumably you can do exactly the same in the Experimental block?

Hi Michael,

So basically, the set up and everything I did was right, I just forgot to activate one of my blocks (the nRep$ was empty, but when I inserted the value 1 there everything run smoothly).

For anyone who has the same problem or who wants to create a similar experiment, here’s a pic that shows the design (I will try and post all the materials ASAP):

.