Reaction times are too large, and negative

OS (e.g. Win10):
PsychoPy version (2023.2.0) - installed by IT across Aston University’s PCs under “Aston Apps”.

What are you trying to achieve?:
Ive built quite a standard lexical decision experiment - and expected the response times to my keyboard components to measure automatically.
What did you try to make it work?:
Created a keyboard component and kept all settings as default. I expected to see the reaction times under “resp.rt” but it seems like jibberish (some numbers are negative) - see pic below

What did you try to make it work?:
I’ve also tried a basic Stroop task using version 2023.2.0 and that produces negative responses too. The Stroop task worked perfectly under previous 2022 versions.

Hi @Ryan_Blything,

It sounds like you might be experiencing the same issue as this post. This was a bug that should now be solved in the latest release (2023.2.3).

Thanks so much,


Hi Kim,
Thanks for your response - yes the bug is fixed when the experiment is run using the latest release (2023.2.3) (the problem for me was that students at my Uni only had access to 2023.2.0 - but fortunately IT have now updated this).

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