Before reading this, look also at the standard SART task ; this is merely a special version of it designed by Professor Gijsbert Stoet. This introduction here is short. Read the SART page to understand the background. This page explains the problems with SART and justifies the extenion.

The original SART is a measure of sustained attention. It is a popular task on PsyToolkit, but it has its problems. In Professor Stoet’s opinion, the main problem is that there is no visual feedback for the participant when pressing the correct button. In this version that happens.

To cite this task, refer to the PsyToolkit articlespapers (Stoet 2010, 2017).

About this implementation

This version changes the color of the mask when the person presses the button correctly (to green). As in the original SART, incorrect responses to digit 3 will lead to an error feedback message.

Run the demo

In this example, you will view digits (1 to 9). Each time when it shows up, it will quickly be masked by a circle with a cross. You need to respond with a space bar, except when it is the digit 3.

Data output file

In PsyToolkit, the data output file is simply a textfile. The save line of the PsyToolkit experiment script determines what is being saved in the data output file. Typically, for each experimental trial, you would have exactly one line in your text file, and each number/word on that line gives you the information you need for your data analysis, such as the condition, response speed, and whether an error was made.

Meaning of the columns in the output datafile. For each trial (there are 18 training trials and 225 "real" trials), there is one line with 6 numbers (columns).

You need this information for your data analysis.

Colum Meaning


name of block


number of the block


go (1) or no-go trial (0)


digit (1-9)


size of the stimulus (values between 1 and 5, from smalles to biggest)


response outcome (0 is error, 1 is correct)


reaction time in milliseconds


If you have a PsyToolkit account, you can upload the zipfile directly to your PsyToolkit account. Watch a video on how to do that. If you want to upload the zipfile into your PsyToolkit account, make sure the file is not automatically uncompressed (some browsers, especially Mac Safari, by default uncompress zip files). Read here how to easily deal with this.

Further reading

  • Robertson, I.H., Manly, T., Andrade, J., Baddeley, B.T., Yiend, J. (1997). 'Oops!': performance correlates of everyday attentional failures in traumatic brain injured and normal subjects. Neuropsychologia, 35(6), 747-758.

  • Ralph, B.C.W., Thomson, D.R., Seli, P., Carriere, J.S.A., Smilek, D. Media multitasking and behavioral measures of sustained attention. Attention, Perception, & Psychophysics, 77, 390-401.

  • Alloway, T. P., & Alloway, R. G. (2012). The impact of engagement with social networking sites (SNSs) on cognitive skills. Computers in Human Behavior, 28(5), 1748-1754.