[solved] Semi random loop for Hebb learning

Sigor16

Hi,

I began to use OpenSesame recently for some experiments and I found it very easy to use but I have little knowledge in Python coding and I think that I will need inline script for the following experiment.

Basically, the participants will hear sequences of tones. The tones are in .mp3 format and set in the file pool, and each sequence is composed of 7 tones. In the loop sheet, each line representing the trials includes the names of the seven tones that must be played.
There is 21 sequences and I would like to run the sequences as follow. There 30 trials, 1 sequences(hebb sequence) is played 10 times and the other 20 sequences are played 1 time each. The hebb sequence might be played every 3 trials (trial 1, 4, 7, ans so on) with between two presentation of the hebb sequence, choosing randomly two sequence in the pool of 20 non hebb sequences.

It looks like a semi random presentation but I don't know how to reach this. Need I python code or manage with different loops is possible ?

Thank in advance for your help,

Simon

sebastiaan

Hi Simon,

There's currently no way to easily implement pseudo-random orders, although this issue has come up a few times here on the forum, and an issue (#272) has been filed for it.

You may want to take a look at this discussion:

• http://www.cogsci.nl/forum/index.php?p=/discussion/310/

It describes a few ways to implement pseudorandomization. As described there, the easiest (but not necessarily most elegant) way is to use an external program to create your lists and simply copy-paste them into OpenSesame. Alternatively, you can create a custom script to enforce your specific constraints.

Cheers!
Sebastiaan

Sigor16

Hi Sebastian,

Thanks for the reply ! :-)

After navigating through the forum I found a way to conduct a semi random presentation of the sequences. It's not the most elegant way but if someone is interested I can publish the script.

Best,

Simon