problem with random feedback

syckology

Hello, I'm a beginner in opensesame and have a problem to implement feedback in the right way.
In my experiment a visual stimuli is presented for a very short moment and the participants have to decide if they have seen the stimuli or not.
What I try to realise is to give positiv feedback (correct=1) 4 times in a block of 48 trails (50% stimuli presented / 50% stimuli absent) and negative feedback (correct=0) once.
Furthermore the negative feedback shoud be shown just after the participants saw positiv feedback twice, to keep motivation high. The 5 of 48 trails in which the feedback should be shown should be picked randomly.
Do you have an idea how to handle that problem?
Thank you very much for your help!
best regards

eduard

Hi,

If you have no other variables that you manipulate systematically within a block, you can create a variable called feedback_presence and set it to no 43 times and to yes 5 times. Inside the block loop, you would then pop from a list of possible feedback values (the list you have to create earlier): feedbackItems = ['neg','neg',''pos','neg','neg']. Then, depeding on the current value of the feedback, you show it in whichever way you want.

Good luck.

Eduard