Presenting pictures in pseudorandom order

Hi,

Here’s a description of the experiment that I am trying to setup using Superlab and would appreciate any help I can get.

Each trial consists of the following: 1) 3 sec fixation cross → 2) Picture of a face (either sad or happy face) displayed for 6 seconds → 3) 500 ms fixation cross → 4) A word that will be displayed until participant responds or if no response occurs within 5 seconds, the next trial begins → 5) 8 second intertrial interval.

Order of pictures presented:
There are two sets of pictures (i.e., 16 sad faces and 16 happy faces) that I would like to present in a pseudorandom order. No more than 3 sad faces or 3 happy faces (chosen randomly from the stimulus list) should be presented in a row. I am not sure how you implement this design. Should the stimulus lists be separate (i.e., one for sad faces and another for happy faces) or should there be only one stimulus list? I am not sure how to setup the macro either.

In the second part of the experiment, I would like participants to view the pictures again but in the exact SAME ORDER as was initially presented but this time, they are asked to rate the picture. How do I make the pictures appear in the exact SAME ORDER as was initially presented?

Note: I have attached the experiment but used text instead of pictures in the stimulus lists.

Unfortunately the second part of your experiment is not possible within SuperLab. For the first part, I do suggest using separate lists, but having them in the same block.

Thanks for your help, Monika! After following the sample experiment found here: http://community.cedrus.com/showthread.php?t=793 (thanks for posting this, it was VERY helpful), I was able to come up with a sample experiment that met the first part of requirements (as described above). However, I am having trouble getting all the trials within each stimulus list to appear. In the sample experiment attached, there are 5 items (i.e., 5 sad faces and 5 happy faces) in each stimulus list and I have duplicated the block five times but I can’t seem to get all the trials (i.e., total of 10 trials) to appear. Any help here would be appreciated.

Can you also kindly confirm that the words that appear from the Word list in my example can never truly be random in the sense that it is always linked to the order of the picture stimulus list? (e.g., if either Sad Pic 5 or Happy Pic 5 is shown, Word 5 will always be displayed)?

acap_testexp2.zip (2.33 KB)

Hi,

I am still having difficulties getting all the trials within each stimulus list to appear. Any help would be greatly appreciated!

Posting Test Experiment

Second test experiment attached.

acaptestexample3.zip (2.88 KB)

I apologize for not getting back to you sooner. Thank you for posting your latest sample. You should have a response shortly.