Selecting Items From Lists

I’m trying to set up an experiment and I have a couple of (long) questions. Here’s a basic description of the experiment I’m trying to run:

I’m doing a spatial memory task with two types of stimuli, ‘separate’ stimuli and ‘together’ stimuli. The separate stimuli are individual lines or squares and the together stimuli are combinations of the lines and squares (e.g., a line on top of a square). In each trial, I want to have 6 total stimuli (so that would be 3 lines and 3 squares in the ‘separate’ group and then 3 combined stimuli in the ‘together’ group). Right now I have 3 lists in SuperLab: Separate Lines (4 total), Separate Squares (4 total), and together stimuli (16 total). My first question is how to I select a subset of a list to present in a trial randomly? For example, in one separate trial how do I set it up to select 3 lines and 3 squares at random to present? I tried just making 6 events (3 line and 3 square) but when I run the experiment it shows the same line/square each time instead of picking the other list items.

I’m presenting the shapes at various locations on the screen based on a trial variable list. So the 6 stimuli should be shown in the positions (study phase), then after a retention interval I need to show a test stimulus. At test, I need a stimulus to be shown in one of the locations used in the original study study phase. Half the time this stimulus should be the same and half of the time it should be different (so one of the other items that wasn’t shown in that location). How would I go about doing that in SuperLab? In other words, how do I get it to remember what was shown and where then use that to present the test stimulus?

I apologize for the length, but I’m testing out the trial version and need to make sure that it can do what I need it to!


Hi Lisa,

This would take me too long to respond to in typing even if assuming I understand 100% what you’re trying to do! Call me at your convenience next week and we’ll try to setup the experiment together.



That sounds great, thank you! What is your phone number?

1-800-cedrus-1 (800-233-7871)