| Reference | Downloads | Github

Stimuli flashing on screen for one frame

URL of experiment: Pavlovia

Description of the problem:

Hello all!
In Pavlovia, I am drawing multiple stimuli to the screen at once. On every trial, there is a polygon that is meant to be partially occluded by another ImageStim component. I’m finding that at the beginning of the epoch, for only about one frame, the polygon is “flashing” on the screen before the second component successfully occludes it. This is highly problematic insofar as it results in additional attention drawn to the side of the screen that the image is flashing on. I am autoDraw’ing both components during that epoch of the trial using custom JS code components, but it doesn’t seem to change the fact that the Polygon is briefly drawn first before the Imagestim. I also tried changing the order that the components are sorted in the Builder GUI for that Routine, but it didn’t seem to make a difference. Notably, this doesn’t happen at every loop of the Routine, only a subset of trials, which makes me wonder if it’s a timing issue.

Any help would be greatly appreciated!

Hi There,

I think you might need to make the experiment public so that we can access it through the link - Searching for experiments on Pavlovia — PsychoPy v2021.2


Done! Sorry for forgetting that!

No worries! OK as a first check, I notice this was made in a much older version of PsychoPy (2020.2) - I recompiled a version using 2021.1.4 here - please could you let meknow if the issue still exists in this version? silent_cereal_builder_ColorShape [PsychoPy]