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Powerpoint presenter-view-like functionality with dual monitor stimuli presentation

Hi everyone,

I doubt this exists, but will ask just in case. I am running an fMRI study with multiple paradigms that are counterbalanced across participants. The stim computer is outside and there is an LCD monitor used inside the magnet room. Ideally, participants don’t see us changing from one paradigm to another. I can do this by choosing screen 2 in the experiment settings. However, if I do this then I am unable to see what the participant is seeing and therefore am blind as to whether the experiment is behaving as it should. If I mirror the main screen then the participant sees us as we switch experiments and they can also see the flow panel.

Is there a way to rig PsychoPy3 to have a PowerPoint presenter-view-like functionality where the participant only sees the stimuli, but the experimenter can see the paradigm and the controls? I am unable to safely turn the inverter from the PC to the MRI monitor on and off unfortunately.


PsychoPy can display stimuli in multiple independent windows, each on a separate monitor. You should make the primary window on the subject’s monitor full-screen, while also displaying stimuli on a secondary window on your monitor that is not full-screen (so you can just park it in the corner while still interacting with other windows).

Builder doesn’t provide this option natively - you’ll need to add some custom code to open a second window. That window should probably have waitBlanking set to False, so it doesn’t muck up the timing on the main window.

You might find it sufficient instead of completely duplicating what the subject sees to just update a text stimulus on that second window - e.g. once per trial, say “Trial 4 of practice block” etc. To completely duplicate what the subject sees, you might be able to monkey patch the main window’s .flip() function to mirror its content to your second window - it would be a bit more tricky.

Thanks Michael! I’ll try these suggestions and once I get it working I’ll post the code here. Had no idea about the level of flexibility with monitors!

For an example, switch to PsychoPy’s Coder mode and from the Demos menu, select stimuli ->