Issues with jsPsych - Pavlovia integration

URL of experiment: Tower of London

Description of the problem: I am trying to make this jsPyshc version of the Tower of London experiment run on Pavlovia:

Sign in · GitLab (forked from Sarah Martin / tower-of-london · GitLab)

I have modified index.html and experiment.js following instructions here: Pavlovia

The modified version is here: Sign in · GitLab

The jsPsych experiment runs fine locally, but I have been unable to make it run on Pavlovia. As soon as I hit the Launch experiment button, I get these errors (and a blank screen is displayed).

I wonder whether this is something to do with the experimenter running an older version of jspsych? Or is it rather that I am not using an up-to-date version of the jspych pavlovia plugin?

This is my first attempt at integrating a jspsych experiment with Pavlovia. Any hint would be greatly appreciated. Please let me know if you need any more information on the errors.

Thank you,


Hey Chiara,

I’ve been doing some upgrades of the jspsych plugin. Take a peek over here: jsPsych Pavlovia plugin · Discussion #1738 · jspsych/jsPsych · GitHub

However, I think this issue is due to something else. To get a better grasp, see this tutorial: Thomas Pronk / tutorial_js_semantic_error · GitLab

Good luck with bug hunting!

Thanks very much for the pointers! Unfortuntely, checking the errors only got me so far. I can see there is an issue with the plugins and I suspect it is down to changes in jspsych plugin syntax along the way. I think newer versions of the pavlovia plugin (or possibly all versions) follow a syntax that is different from the one of the custom plugins this experiment relies on - it was probably created in an older version of jspysch and relies on the syntax used by that version. I don’t have enough knowledge of jspsych/js to start editing the custom plugins, so I think my best option is to run this experiment on my own server rather than Pavlovia.

Ah, that sounds like an interesting programming problem. Which indeed tends to mean “let’s not go there” for many people :).

I’m a bit busy at the moment, but I will take a peek at my best opportunity.

@gambic, could you make me a maintainer or developer of your gitlab repo? I’d like to take a quick peek if that’s OK

@thomas_pronk - apologies I did not see your reply until now. I have given you access as a developer. I have now moved the task to my own server though and it works fine there, so no rush!

Thanks for sharing! I wondered whether your task is based on jspsych 7.x , which introduced some major changes that might have problems with my plugin. However, yours is based on jspsych 6.x, so that ain’t it. No matter though; since you’ve got it working (on your own server, no need for me to dive deeper for now.

Happy experimenting!