The stop-signal task is an essential tool for studying response inhibition and impulse control. In this task, participants typically perform a go task (e.g. press left when an arrow pointing to the left appears, and right when an arrow pointing to the right appears), but on a minority of the trials, a stop-signal (e.g. crosses replacing the arrow) appears after a variable stop-signal delay (SSD), instructing participants to suppress the imminent go response. The stop-signal task is unique in allowing the estimation of the covert latency of response inhibition (stop-signal reaction time or SSRT).
Here we provide open-source software that can be used to execute a stop-signal task and analyze the resulting data, in an easy-to-use way that complies with the recommendations described in "Capturing the ability to inhibit actions and impulsive behaviors: A consensus guide to the stop-signal task" (Verbruggen et al., 2019).
We provide platform-independent software to correctly execute the stop-signal task. It is programmed using jsPsych (De Leeuw, 2015)
The software is easily amendable, and can be used for offline and online studies. It replaces a previous version (described in Verbruggen, Logan, & Stevens, 2008) which is no longer maintained (and which could only be used on Windows computers).
To install the stop-signal task, download the jsPsych folder. We strongly recommend that you read the README-STOP-IT-JS file before you start. To run the stop-signal task, simply open 'experiment.html' in Firefox or Chrome browser, and follow the instructions.
Data collected with the jsPsych version of STOP-IT can be analyzed with an 'R Shiny' app. For detailed information about installation and usage of the analysis app, please read the README-ANALYZE-IT-JS file.
Data collected with the original Tscope version of STOP-IT can be analyzed with a different R shiny app. This app replaces the original ANALYZE-IT program (Verbruggen, Logan, & Stevens, 2008), which no longer complies with the most recent recommendations (so this 2008-version should no longer be used!). Please read the README-ANALYZE-IT-Tscope file for further information about installation and usage.
For questions or feedback, contact frederick.verbruggen@ugent.be
de Leeuw, J. R. (2015). jsPsych: A JavaScript library for creating behavioral experiments in a Web browser. Behavior Research Methods, 47(1), 1–12. https://doi.org/10.3758/s13428-014-0458-y
Verbruggen, F., Logan, G. D., & Stevens, M. A. (2008). STOP-IT: Windows executable software for the stop-signal paradigm. Behavior Research Methods, 40(2), 479–483. https://doi.org/10.3758/BRM.40.2.479
Verbruggen, F., Aron, A. R., Band, G. P., Beste, C., Bissett, P. G., Brockett, A. T., … Boehler, C. N. (2019). A consensus guide to capturing the ability to inhibit actions and impulsive behaviors in the stop-signal task. ELife, 8, e46323. https://doi.org/10.7554/eLife.46323