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Is the builder response time assessment aligned to the screen refresh rate?

I have a question about timing of responses. The builder provides the option to include code that is run each frame. 1) That means, depending on the monitor, the code runs (e.g.,) every ~16 ms, right? 2) When I “compile” the builder experiment into a python script, the code that was included in the “each frame” component appears at the same location where I also find the code of the builder-implemented button response (while continueRoutine…). 3) Does that mean, the builder-implemented button response has the same “resolution” as the frame rate – probed for only every ~16 ms?

How does the “sync RT with screen” option relate to this? What happens if I uncheck this option?
Thanks a lot,

does the lack of responses suggest that I’m asking my question in a wrong way? There is obviously information on timing of stimulus presentation in the psychopy help – with the obvious limitation that stimuli can only be presented in sync with the screen refresh rate. However, I could not find something similar about response times. I appreciate any help, pointing me to online resources or help me understand what is going on.

No, it just slipped under the radar I guess.

Your intuition about the time resolution of Builder keypress timing was true until recently (introduced in version 3.1 and really solidified in version 3.2). At that point, Builder switched from using PsychoPy’s own event module for collecting keypress events to the new Keyboard class, using code ported from the Psyctoolbox project by Mario Kleiner. Now, although the code still runs just once every screen refresh, the keyboard responses have a time stamp that corresponds to when the key was actually pushed, rather than when the code ran to check it.

As I understand it though, the 16 ms resolution issue will still apply to other code that runs once every screen refresh, including getting mouse button responses.

Okay, thank you. Could I have known about this?

Thank you!
I appreciate your help and all the voluntary work around PsychoPy!

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