"Condition expression" issue (stroop-like task)

In a stroop-like task, I would like to set some “condition expression” options in order not to have repetition of color or word dimension from a trial to another.
I created some variables (I have four words and four colors) and set condition expression for each trial :
For instance, when a trial color is BLUE, I set the following condition expression in the when to present frame :
“Current trial’s code value is not set up to color (variable) BLUE”. Si that I hope to obtain a different color in each trial.

The problem is that, when I set this up for all of the events, it does not seem to work : when I start the experiment, nothing happens and it seems that there isn’t any trial that suits condition expression and that can be “presented”.

Anyway, there may be a better way to control a trial-to-trial (no-)repetition.

I hope you understood the issue since I’m not a native english :slight_smile:


Can you please post your experiment as an Experiment Package? This is found under the File menu within SuperLab.

Presently, I haven’t got the right computer with me (the “Superlab” one !). I’ll post the experimental package soon.

Thank you,


Here is my experimental package, thank you for watching :slight_smile:
Actually, it is not a definitive version but if I succeed in launching this “192” block, I’ll be able to keep on working.
I aim to have no “trial-to-trial” repetition for “word” and “font” variables.



wordfont.zip (6.76 KB)

wordfont.tgz (6.54 KB)

I apologize for the delay in getting back to you. Attached is your experiment with some modifications which are explained below. It is recommended that you use stimulus lists for your events in the future. Since we modified only the first trial, I couldn’t verify 100% that the changes would work, but they should.

  • A code was created named "Last Color Used" with the values being all four of your colors
  • Four macros were created to check for the last color presented. The first macro is "Check if last presented color is "Bleu"

  • Under the [B]Expression[/B] tab: "Number of Trials Presented in This Block is equal to 1 trials (Using only the last 1 trials in the block and Trials marked with the code "Couleur"equal to "Bleu")
  • For the[B] If True[/B] tab: Change the value of code "Last Color Used" to "Bleu" in all trials in this block

Within the Trial Editor only the first trial “R1V1” has the modifications.

  • Under [B]When to Present[/B] in the [B]Trial Editor[/B]: "Number of times this trial has been presented is equal to 0 and Current trial's code "Last Color Used" is not set to "Rouge"

wordfontrev.sl4 (88.4 KB)