Instructions before the first trial

Apologies for the 2nd post in quick succession.

I have an experiment in which conditional branching is used to send male participants to a Male block and female participants to a Female block. There are several trials in each block, which I would like to be presented in a random order.

My problem is that the different trials are visually similar but require different responses, and I don’t want participants to get confused. Ideally each trial would begin with a set of instructions. For example - a participant specifies that he is male, then sees the instructions for Trial 1 (the trial is randomly selected), responds to all the stimuli listed for that trial, then sees the instructions for Trial 2, and responds to all stimuli for that trial.

But if I add an ‘instruction’ event at the head of Trial 1 / 2 it will appear every time that trial begins. And if I add a separate trial to display the instructions, I can no longer randomize the order of the trials (I need to keep them non-randomized to keep Trial 1 Instructions before Trial 1).

Is there any way to randomly present Trials but to have an instructions event occur only before the first trial?


Rather then using conditional branching, have you explored the option of using participant groups? With participant groups you can specify which blocks are used for males and which blocks are used for females. The ability to organize your trials into multiple blocks should simplify the organization of your trials. The participant group is selected when you go to run the experiment.

Thanks, Monica. I was not aware of that feature.

I’ve switched the experiment from conditional branching to participant groups, but I’m still finding it difficult to work out how this can make my organization easier.

I’ve attached a sl4 file to demonstrate the set up of my experiment.

What I would like to do is randomize the order of the blocks and trials while keeping the instruction events at the start of each trial. At the moment this is totally beyond me - I could create multiple participant groups with different block orders for each, but this seems overcomplicated.

I’m sure I’m missing something very obvious…

baub_ex.sl4 (9.23 KB)

Please see the attached revised experiment. Make sure to look under the Experiment tab, then Participant Groups. Here you will see the Female and Male Participant groups. I didn’t know how you wanted these to be set up, but you should get the idea from what I have done so far. Please note, when you run the experiment, the window that pops up has a selection called Participant Groups, here you can select either Male or Female Participants. I hope this helps you with what your trying to achieve.

Monika(baub_ex) .sl4 (9.4 KB)

Thanks, Monika

I can’t check this right now because my home computer doesn’t have SL installed, so you may already have sorted this out in the revised expt.

But the main problem I have isn’t organizing people into groups, but instead making sure that each participant receives the trials in a random order. I don’t think this would be an issue if it weren’t for the fact that I need instructions before each trial.

I ‘could’ counterbalance presentation order by making multiple participant groups, but I would really prefer not to go this route because the number of trials in my actual experiment (the attached file is just an example) is quite large, so the number of possible trial orders is pretty big.

If you have already addressed this, apologies!

Using participant groups should ensure the instructions will be shown. It will work as long as the instructions are in a separate block. Trials can be randomized within a block, but not the block themselves.