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Stimulus timing accuracy in PsychoPy – an update, and an example of open science in action

A few days ago I reported on a new paper that tested the timing accuracy of experimental software packages. The paper suggested that PsychoPy  had some issues with presenting very fast stimuli that only lasted one (or a few) screen refreshes.

However, the creator of PsychoPy (Jon Peirce, of Nottingham University) has already responded to the data in the paper. The authors of the paper made all the data and (importantly) the program scripts used to generate it available on the Open Science Framework site. As a result it was possible for Jon to examine the scripts and see what the issue was. It turns out the authors used an older version of PsychoPy, where the ability to set a stimulus duration in frames (or screen refreshes) wasn’t available. Up-to-date versions have this feature, and as a result are now much more reliable. Those who need the full story should read Jon’s comment (and the response by the authors) on the PLoS comments page for the article.

So, great news if, like me, you’re a fan of PsychoPy. However, there’s a wider picture that’s revealed by this little episode, and a very interesting one I think. As a result of the authors posting their code up to the OSF website, and the fact that PLoS One allows comments to be posted on its articles, the issue could be readily identified and clarified, in a completely open and public manner, and within a matter of days. This is one of the best examples I’ve seen of the power of an open approach to science, and the ability of post-publication review to have a real impact.

Interesting times, fo’ shiz.