Stroop Squared Task

Background

The Stroop Squared Task is an adaptation of the popular cognitive-behavioral Stroop Task. It belongs to a battery of Squared Tasks consisting of variants of three classic cognitive-behavioral tests measuring cognitive control and interference resolution. In addition to the Stroop Squared Task, the battery also runs the Flanker Squared Task as well as the Simon Squared Task.

The 'Squared' battery was developed by Alex Burgoyne, Jason Tsukahara, Randall Engle and colleagues in 2023 to simplify and speed up task administration as well as increase the level of conflict in each of those three tasks (aka 'squaring' the conflict). The user interface as well as instructions and scoring were streamlined, and each test can be completed in under 3 minutes.

The original Stroop Task presents a color word like RED printed in different colors (e.g. RED) and participants are asked to name the color of the word. This setup presents one possible response conflict - the potential conflict between the meaning of the word and the color it's presented in - that the participant has to resolve when responding.

The Stroop Squared Task increases the conflict by presenting the target word (the word RED or BLUE, printed in either red or blue) and providing two response buttons with the labels RED or BLUE printed in either red or blue. The task is to match the color of the target word with the meaning of the response button label. Thus, participants not only have to resolve the conflict between matching the response to the target by surface appearance alone but also have to resolve the conflicts between meaning and color of both, the target word and the response button labels.

The Millisecond implementation of the Stroop Squared Task provides 6 versions: five versions that run different fixed trial sequences and one randomizing version.

Task Procedure

After learning about the task, participants work on a practice session for 1 minute to familiarize them with the procedure. The target word is presented in the center the screen. The response buttons with the labels RED or BLUE (printed in eithe red or blue) are displayed below. Participants are asked to match the color of the target word to the meaning of the response button labels. Responses are made with the computer mouse or -on touchscreens- by touching the response displays. After the conclusion of the practice session, instructions are reviewed and the test session begins. Each arrow display stays on until a response is made. Visual and auditory feedback is given for each response (200ms) before the next display is presented. Correct responses increase the score; incorrect responses decrease the score. The total score as well as a timer is visible on screen during the duration of the testing session. The testing session terminates after 1.5 minutes.

What it Measures

The Stroop Squared Task measures cognitive control and interference resolution

Psychological domains

• Cognitive Control: Ability to quickly adapt one's thoughts and behavior to current demands
• Inhibitory Control / Response Inhibition: Ability to override automatic responses that interfere with one's goals
• Cognitive Flexibility: Ability to quickly change between different task demands
• Working Memory: Ability to store and manipulate information in short-term memory

Main Performance Metrics

• Net Score: the number of net points earned during the test phase as the main measure of an individual's cognitive control

Psychiatric Conditions

As of this date, the Squared Task battery is relatively new and has mostly been used for research studies with healthy adults.

Test Variations

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Stroop Squared Task.

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Burgoyne, A. P., Tsukahara, J. S., Mashburn, C. A., Pak, R., & Engle, R. W. (2023). Nature and Measurement of Attention Control. Journal of Experimental Psychology. General, 152(8), 2369–2402. https://doi.org/10.1037/xge0001408