Video tutorials
Narrated walkthroughs of Open Lab and of building tasks in the lab.js builder. Each has subtitles in 12 languages, chapters and a transcript, the files to follow along directly under the player, and a link to its docs page.
Files for this video
- ↓ to-open-lab.jsonThe builder file this video starts from (the end of the previous video).
- ↓ media.jsonThe builder file at the end of this video: the pictures, the sound and its Timeline item, inside the file.
- ↓ blue.pngThe picture for blue trials: a shaded blue ball, 240 × 240 pixels, made for this series.
- ↓ green.pngThe picture for green trials: a shaded green ball, 240 × 240 pixels, made for this series.
- ↓ error.wavThe sound after a practice error: two low tones, 250 ms, made for this series.
The lab.js builder: a reaction-time task, step by step
Pictures and sounds
3:41 · narrated, with subtitles in 12 languages · recorded in November 2026
Pictures in place of the drawn circles, added on a screen's folder icon and picked by a placeholder from trial_type, and a short sound after each error in the practice, played by the Timeline with a gain that mutes it otherwise; previewed, saved, and updated on Open Lab with its files.
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