Presenting target and supressor on two screens


I want to present two stimuli (suppressor on the right side and target on the left side) simultaneously. I want to set 10 hz refresh rate for the suppressor, and 1 second for target stimuli which should started at 3 second after the experiment begin. I set the locations of targets by changing positions in the same routine where two targets are expected to present simultaneuously. I have created the routine for the suppressor target and it works properly when it works without the target. But when I add the target (e.g. any text which is presented on the left side of the screen) supressor is got broken. It doesn’t work properly and refresh rate which should be 10 hz crashes. I am adding the file, maybe somebody can help me.
Suppressor targets: (4.2 MB)

builder and excel file: (14.3 KB)

I am not sure what you are trying to do, but adding a text component to your experiment works fine for me. What error do you encounter?

By the way, to achieve a refresh rate of 10Hz, you have to set the duration of the images to 0.1 second.

I want to present the suppressor like this =

but when i add the text component on the left screen, it doesn’t work as I want. =

I want to present “xxx” while the suppressor which is presented on the right screen rapidly changing. My question is when i set 0.1 second for the suppressor, what should I do for the text’s timing?

You have to set the text to .1 sec as well.

but I don’t want to present the text as rapidly as the supressor, it should be presented more slower.

I think you should maybe go back and work through some PsychoPy tutorials first to understand, how routines and loops work.

Your routine is always as long as its longest component. Only after all components are finished will the next repetition in the loop begin. So if you set the duration of the text to be longer than the image (e.g., 1 sec), you will see the text for 1 sec and the image for the first .1 sec of that second. Then, the next repetition begins, again showing the text for 1 sec and the image for the first .1 sec of that second.

yes and that’s the main problem for me. I have known that the routine is always as long as its longest component but in my example, I have to set the suppressor for 0.1 sec (10hz) in the routine. On the other hand, I also have to set the text component which should be longer than the suppressor (e.g., 1 sec). In this case, I know that the routine duration depends on the component which is the longest one. I guess I shouldn’t add these two component (text and suppressor) in the same routine because of the timing. Because I am wanting to present the suppressor for 10 Hz, across the experiment.

No, you still can add both to the same routine. But you have to set up in a way, that the target is the same for 10 trials (10 presentations of a suppressor). Here is a little example what this could look like: (19.0 KB)


I created a little toy-example using text as target and suppressor which doesn’t need trials for the suppressor presentation. Adapt to your needs.

TargSup.psyexp (11.7 KB)

It is an adaptation from a change blindess-experiment. The code for this came from WakeCarter.

Best wishes Jens

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I have to present the suppressors as images and the target will be random numbers that will also be imported from an excel file. So I guess i should use the loops in any case. But do I need to change the codes or not? I am not very good at coding, unfortunately. Here is the stimulus that I will use. (4.2 MB)

Hello bbbb

you need to explain your experiment in much more detail before anybody can help you. Tired to be as explicit as in a Methods section of an manuscript.

You have 1000 Modrians in your Excel-file but only 7 numbers (0, 1, 2, 3, 4, 5, 8). How do the number and the Modrians are related to each other? Do you want to use only these seven numbers.

Best wishes Jens