Executive Function
Slips-of-Action Task
Also called: slips of action test, fabulous fruit game, outcome devaluation task, instrumental devaluation task
Measure the balance between goals and habits: participants learn which key opens each fruit box, then press quickly only for boxes whose fruit still pays.
11-13 minTimed: desktop or laptop with a mouse or trackpad
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Preview any test free after you sign up.
- Papers, 2021 to 2025
- 31
- Evidence grade
- C
- Registered clinical studies
- 3
What it measures
Measures the balance between goal-directed and habitual control of action. Participants learn which key opens each fruit box to win the fruit inside, then some fruits stop paying and boxes come quickly. The main score is the devaluation sensitivity index: the share of responses to boxes whose fruit still pays minus the share to boxes whose fruit no longer does.
Constructs
- Goal-directed control
- Habit
- Instrumental learning
- Outcome devaluation
Research uses
- Research on habits and compulsivity
- Obsessive-compulsive disorder and addiction research at the group level
- Within-study comparison of goal-directed and habitual responding
How the paradigm works
The slips-of-action task measures the balance between goal-directed actions, chosen for what they bring, and habits, set off by what a person sees (de Wit and colleagues, 2007; Gillan and colleagues, 2011). Participants first learn by trial and error which of two keys opens each of six boxes; the right key wins the fruit inside, with points. Then some fruits stop paying. In the slips-of-action test the boxes come quickly, and the participant should press only for boxes whose fruit still pays. A press for a box whose fruit was crossed out is a slip of action: the habit to open that box won over knowing that its fruit no longer pays. Gillan and colleagues found more slips in people with obsessive-compulsive disorder than in comparison participants, and more slips with more severe symptoms.
More about the paradigm
The six boxes form three pairs, one box for each key. In the standard pair, four different fruits are on the doors and inside. In the congruent pair, each box holds the fruit on its door. In the incongruent pair, each fruit is on one box's door and inside the other box, so recalling the fruit points to the wrong key, and people tend to learn these boxes as habits (de Wit and colleagues, 2007). Training runs 6 blocks of 12 boxes (4 to 8 in the settings), and the right key earns 5 points within 1 second, down to 1 point after 2.5 seconds. An outcome-devaluation test then shows two open boxes, one fruit crossed out, and asks for the key that won the other fruit, with no feedback. The slips-of-action test and a baseline test follow, in an order drawn for each session. Each has 6 blocks of 12 boxes: a 5 second screen shows the six fruits found inside (slips test) or the six boxes (baseline test) with two crossed out, then each box stays for 1 second (2 in the settings) with a 1 second blank after it. In the baseline test the crosses are on the boxes themselves, so no knowledge of the fruit is needed, and the test shows how well a person follows the same quick rule (de Wit and colleagues, 2012). At the end, the participant chooses the fruit that was inside each box. The fruit are pictures from Noto Emoji, and which fruit plays which role comes from the session's seed. About 11 to 13 minutes, on a computer with a keyboard.
The main score is the devaluation sensitivity index: in the slips-of-action test, the share of boxes whose fruit still pays with a key press minus the share of boxes whose fruit was crossed out with a key press. A higher index means more goal-directed control, and slips lower it. The slip rate, the index for each pair, the same index in the baseline test, the outcome-devaluation test accuracy, training accuracy and the fruit chosen at the end come next. A session with under 75% right in the last training block, or with presses for fewer than half the boxes that still pay, is flagged for review. Scores support research and do not diagnose.
Scores
- Devaluation Sensitivity Index%
- Slips-of-action test: the share of boxes whose fruit still pays with a key press, minus the share of boxes whose fruit was crossed out with a key press.
- Higher means more goal-directed control; 0 means pressing regardless of the fruit's value
- Slip Rate%
- Share of boxes whose fruit was crossed out with a key press, in the slips-of-action test.
- Lower is better: these presses are the slips of action
- Presses for Fruit That Still Pays%
- Share of boxes whose fruit still pays with a key press, in the slips-of-action test.
- Under 0.5 is flagged for review
- Right Key for Fruit That Still Pays%
- Share of boxes whose fruit still pays opened with the right key, in the slips-of-action test.
- Higher is better
- Devaluation Sensitivity, Standard Pair%
- The index for the two standard boxes, whose four fruits differ.
- Higher means more goal-directed control
- Devaluation Sensitivity, Congruent Pair%
- The index for the two congruent boxes, which hold the fruit on their doors.
- Higher means more goal-directed control
- Devaluation Sensitivity, Incongruent Pair%
- The index for the two incongruent boxes, where each fruit is on one box's door and inside the other box.
- Usually lowest: these boxes tend to be learned as habits
- Baseline Test Sensitivity%
- Baseline test: the share of boxes without a cross with a key press, minus the share of crossed boxes with a key press.
- Higher is better; it needs no knowledge of the fruit
- Baseline Test Slip Rate%
- Share of crossed boxes with a key press, in the baseline test.
- Lower is better
- Outcome-Devaluation Test Accuracy%
- Share of the 12 outcome-devaluation questions answered with the key that won the fruit without a cross.
- Higher means more knowledge of what each key won; 0.5 is chance
- Outcome-Devaluation Test, Standard Pair%
- Accuracy on the 4 questions about the standard pair.
- 0.5 is chance
- Outcome-Devaluation Test, Congruent Pair%
- Accuracy on the 4 questions about the congruent pair.
- 0.5 is chance
- Outcome-Devaluation Test, Incongruent Pair%
- Accuracy on the 4 questions about the incongruent pair.
- 0.5 is chance; often near it
- Training Accuracy%
- Share of training boxes opened with the right key.
- Higher is better; 0.5 is chance
- Last Training Block Accuracy%
- Share of boxes opened with the right key in the last full training block.
- Under 0.75 is flagged for review
- Median Training Response Timems
- Median time from a box's onset to the right key in training.
- Informational
- Fruit Inside Known%
- Share of the six boxes for which the fruit inside was chosen at the end.
- Higher is better; 1 in 6 is chance
- Median Quick Response Timems
- Median time from a box's onset to the right key, for boxes whose fruit still pays, in the slips-of-action test.
- Informational
- Slips Test First0/1
- 1 when the slips-of-action test came before the baseline test; the order is drawn for each session.
- Informational
- Points Wonpoints
- Points at the end: training, the outcome-devaluation test and the two quick tests.
- Informational
- Anticipationscount
- Presses within 100 ms of a box or a question. In training and the questions they are not taken; in the quick tests they count as neither a response nor a slip.
- Quality check
- Quick Test Boxes Showncount
- Boxes shown in the slips-of-action and baseline tests in the scored run.
- Fewer than planned is flagged for review
- Planned Quick Test Boxescount
- Boxes planned for the two quick tests: 6 blocks of 12 each.
- Informational
Use and evidence
31 papers from 2021 to 2025 name this task in their title or abstract, up 72% compared with 2016 to 2020. That ranks it 299 of 395 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 13 |
| 2024 | 5 |
| 2023 | 2 |
| 2022 | 4 |
| 2021 | 7 |
| 2020 | 4 |
| 2019 | 2 |
| 2018 | 4 |
| 2017 | 4 |
| 2016 | 4 |
| 2015 | 0 |
| 2014 | 1 |
| 2013 | 2 |
| 2012 | 1 |
| 2011 | 4 |
| 2010 | 2 |
| 2009 | 0 |
| 2008 | 3 |
| 2007 | 1 |
| 2006 | 2 |
| 2005 | 3 |
| 2004 | 0 |
| 2003 | 0 |
| 2002 | 1 |
| 2001 | 2 |
| 2000 | 0 |
Use grade D
30 to 99 papers from 2021 to 2025.
Evidence grade C
At least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies.
- Papers on test-retest reliability
- 0
- Papers on reliability or validity
- 4
- Registered clinical studies using it as an outcome
- 3
Note on the counts: a few counted papers describe everyday action slips.
How the grades work
Use: A is 1,000 or more papers from 2021 to 2025, B 300 to 999, C 100 to 299, D 30 to 99 and E fewer than 30. Evidence: A means at least 25 papers report its test-retest reliability and at least 25 registered clinical studies use it as an outcome; B, at least 8 test-retest papers, and either 5 registered clinical studies or 150 reliability or validity papers; C, at least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies; D, little published measurement evidence found. The counts measure use. They include every paper that names the task in its title or abstract. Grades describe the published research on this task, not ConductCognition's version of it.
Source: ConductCognition test census 0.14.0, counted 2 November 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Fruit
- 8 fruit pictures from Noto Emoji, a freely licensed set, each worth the same points; which fruit plays which role is drawn for each session. Practice uses 4 drinks.
- Boxes
- 6 boxes with a fruit on each door, in 3 pairs of one F box and one J box: standard (four different fruits on the doors and inside), congruent (each box holds the fruit on its door) and incongruent (each fruit is on one box's door and inside the other box).
- Training
- 6 blocks of 12 boxes (standard; 4 to 8), each box twice per block in a seeded order, with no time limit. The right key opens the box and shows the fruit inside with 5 points under 1,000 ms, 4 under 1,500 ms, 3 under 2,000 ms, 2 under 2,500 ms and 1 after that; the other key shows an empty box. The open box shows for 1,000 ms, then a 500 ms blank.
- Outcome-devaluation test
- 12 trials: two open boxes holding the two fruits of one pair, one crossed out, and the key that won the other fruit as the answer. Each fruit is crossed twice and shown on each side, with no feedback and no time limit. 2 examples with drinks and feedback come first.
- Slips-of-action test
- 6 blocks of 12 boxes, each box twice per block. Each block starts with the six fruits found inside the boxes for 5,000 ms, two of them crossed out, from different pairs and keys, so each fruit is crossed in 2 blocks; then a 1,000 ms blank. Each box stays for 1,000 ms (standard; or 2,000 ms) whatever is pressed, with a 1,000 ms blank after it. The right key for a fruit that still pays earns 1 point, and a press for a crossed fruit costs 1.
- Baseline test
- The same, with the six boxes shown and two boxes crossed out in place of fruit. The order of the two quick tests is drawn for each session.
- Questions
- At the end, for each box, which of the six fruits was inside it, with no feedback.
- Points
- Shown during training and in total at the end. Money is mentioned only if the study turns on the payment line.
- Practice
- 4 boxes with drinks on their doors, with the same feedback as training.
The design follows Gillan and colleagues (2011), with the three pairs of de Wit and colleagues (2007) and the baseline test of de Wit and colleagues (2012). Blocks hold 12 boxes in place of 24 and the screen of crosses shows for 5 seconds in place of 10, to keep the session near 12 minutes. A press in the first 100 ms of a box counts as neither a response nor a slip. Slips depend on time pressure, so compare sessions with the same time per box. The scores support research and do not diagnose.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: slips_of_action_slips_test and slips_of_action_baseline_test from the scored run, a press of the box's key required on boxes that still pay and withheld on crossed ones. Presses concentrated on the crossed boxes invalidate, and presses that do not separate the two kinds of box are flagged. Misses are what the short window produces, so only a session with no presses is invalid and a long run of misses is flagged. Presses under 100 ms on more than max(2, 20%) of the scored boxes invalidate. Under 75% right in the last training block, presses for under half the boxes that still pay in the slips-of-action test, and a run short of its planned boxes are flagged for review and withhold the percentile.
Why these rules
Responses concentrated on trials that needed none (one-sided Fisher exact test, p < .05) mean the instructions were reversed and invalidate; responses that do not separate the two trial types are flagged. Missed targets are what this test measures, so missed responses never invalidate on their own. A session with no responses is invalid. An unbroken run of misses covering at least half the response trials (minimum 8) may mean the participant stopped, so the session is flagged and its percentile withheld. The two quick tests are scored together so that a participant who stopped following the task in either is caught: one with habits still separates the boxes in the baseline test, where the crosses are on the boxes themselves (de Wit and colleagues, 2012). Studies of this task leave out participants who did not learn the training stage (Worbe and colleagues, 2015), and a slip rate means little without presses for the boxes that still pay. Missed responses and responses under 100 ms keep the platform's timed-test rule: more than max(3, 25%) missed responses or more than max(2, 20%) responses under 100 ms invalidate, and any is flagged. A response under 100 ms cannot be a reaction to the stimulus.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Training blocks | 6 | 4 to 8 |
| Time per box in the quick tests | 1 second (standard) | 1 second (standard), 2 seconds |
| Payment line | Hypothetical points (standard) | Hypothetical points (standard), The study pays for points |
Yearly plans can change settings within these limits. Free and pay-as-you-go studies use the standard settings.
Need a setting this test does not have?
Devices and languages
- Timed test: participants need a desktop or laptop with a mouse or trackpad. Participant devices
- Languages: English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese.
- Available on: Every plan, including the free plan.
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite and describe
Participants completed the Slips-of-Action Task in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; de Wit et al., 2007; Gillan et al., 2011), with the standard settings (training blocks: 6; time per box in the quick tests: 1 second; payment line: Hypothetical points). The main score was devaluation sensitivity index (slips-of-action test: the share of boxes whose fruit still pays with a key press, minus the share of boxes whose fruit was crossed out with a key press).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- de Wit, S., Niry, D., Wariyar, R., Aitken, M. R. F., & Dickinson, A. (2007). Stimulus-outcome interactions during instrumental discrimination learning by rats and humans. Journal of Experimental Psychology: Animal Behavior Processes, 33(1), 1-11. https://doi.org/10.1037/0097-7403.33.1.1The fruit boxes and the standard, congruent and incongruent pairs.
- Gillan, C. M., Papmeyer, M., Morein-Zamir, S., Sahakian, B. J., Fineberg, N. A., Robbins, T. W., & de Wit, S. (2011). Disruption in the balance between goal-directed behavior and habit learning in obsessive-compulsive disorder. American Journal of Psychiatry, 168(7), 718-726. https://doi.org/10.1176/appi.ajp.2011.10071062Training points by speed, the outcome-devaluation test and the slips-of-action test.
- de Wit, S., Watson, P., Harsay, H. A., Cohen, M. X., van de Vijver, I., & Ridderinkhof, K. R. (2012). Corticostriatal connectivity underlies individual differences in the balance between habitual and goal-directed action control. Journal of Neuroscience, 32(35), 12066-12075. https://doi.org/10.1523/JNEUROSCI.1088-12.2012The baseline test, crossed pairs from different pairs and keys, and the difference score.
- Worbe, Y., Savulich, G., de Wit, S., Fernandez-Egea, E., & Robbins, T. W. (2015). Tryptophan depletion promotes habitual over goal-directed control of appetitive responding in humans. International Journal of Neuropsychopharmacology, 18(10), pyv013. https://doi.org/10.1093/ijnp/pyv013Eight training blocks and the baseline test as a check of response inhibition.
- Watson, P., Gladwin, T. E., Verhoeven, A. A. C., & de Wit, S. (2023). Investigating habits in humans with a symmetrical outcome-revaluation task. Behavior Research Methods, 55(5), 2687-2705. https://doi.org/10.3758/s13428-022-01922-4Limits of the task, and a design that tests habits in both directions.
Source papers
- Gillan CM, Papmeyer M, Morein-Zamir S, Sahakian BJ, Fineberg NA, Robbins TW, de Wit S (2011). Disruption in the balance between goal-directed behavior and habit learning in obsessive-compulsive disorder. American Journal of Psychiatry, 168(7):718-726.N 51, Adults
- No normative data for this task.Paradigm source, N/A
Questions
How long does the Slips-of-Action Task take?
About 11 to 13 minutes, as listed in the test library.
What device does a participant need?
Timed test: participants need a desktop or laptop with a mouse or trackpad. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Devaluation Sensitivity Index, Slip Rate, Presses for Fruit That Still Pays, Right Key for Fruit That Still Pays, Devaluation Sensitivity, Standard Pair, Devaluation Sensitivity, Congruent Pair, Devaluation Sensitivity, Incongruent Pair, Baseline Test Sensitivity, Baseline Test Slip Rate, Outcome-Devaluation Test Accuracy, Outcome-Devaluation Test, Standard Pair, Outcome-Devaluation Test, Congruent Pair, Outcome-Devaluation Test, Incongruent Pair, Training Accuracy, Last Training Block Accuracy, Median Training Response Time, Fruit Inside Known, Median Quick Response Time, Slips Test First, Points Won, Anticipations, Quick Test Boxes Shown and Planned Quick Test Boxes. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Slips-of-Action Task used in research?
31 papers from 2021 to 2025 name it in their title or abstract, up 72% compared with 2016 to 2020. That ranks it 299 of 395 test families in the ConductCognition test census (use grade D). Source: ConductCognition test census 0.14.0, counted 2 November 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Slips-of-Action Task have?
In the published research, 0 papers report its test-retest reliability and 3 registered clinical studies use it as an outcome (evidence grade C in the ConductCognition test census).
Which settings can a researcher change?
Training blocks (4 to 8), time per box in the quick tests (1 second (standard), 2 seconds) and payment line (Hypothetical points (standard), The study pays for points). Settings can be changed on yearly plans; free and pay-as-you-go studies use the standard settings.
Which languages can participants use?
Participants can take this test in English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese. English is on every plan, and the other languages come with yearly plans. Have a native speaker read the machine-translated text before launch.
Is this a clinical test?
No. ConductCognition is for research use only. It runs, scores and exports the test; clinical interpretation is outside the platform.
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