Executive Function
Instructed Lying Task
Also called: instructed deception task, cued lying task, Sheffield lie test paradigm
Measure the extra time needed to give an instructed opposite answer to a simple fact question.
4-7 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. Try it here first, with no account.
- Papers, 2021 to 2025
- 6
- Evidence grade
- D
- Registered clinical studies
- 0
What it measures
Measures the response-time cost of giving a cued opposite answer to a simple fact question. The same questions appear under truth and lie cues; scores compare correct response times and accuracy.
Constructs
- Response conflict
- Cognitive control
- Cued response reversal
Research uses
- Cognitive control research
- Instructed deception experiments
- Within-study condition comparisons
How the paradigm works
Giving the opposite of a known answer requires holding the fact in mind while choosing a conflicting response. The Instructed Lying Task measures that response cost with simple yes/no facts. A cue says whether to answer truthfully or give the opposite answer. The same facts occur under both cues, balancing the questions and required keys.
More about the paradigm
This version uses 16 original questions in each of eight languages, four separate practice questions, and two 32-trial blocks by default. The primary score subtracts mean correct truth-cue response time from mean correct lie-cue response time. Accuracy, usable trial counts and a secondary cue-switch cost accompany it. Incorrect answers, anticipations under 100 ms and answers after the deadline do not enter time means.
Scores
- Lie Costms
- Mean correct lie-cue time minus mean correct truth-cue time.
- Positive values mean slower opposite answers
- Truth Mean Response Timems
- Mean correct truth-cue time from 100 ms through the deadline.
- Read with accuracy
- Lie Mean Response Timems
- Mean correct lie-cue time from 100 ms through the deadline.
- Read with accuracy
- Truth Accuracy%
- Share of truth trials answered correctly, including timeouts in the denominator.
- Higher means more answers followed the cue
- Lie Accuracy%
- Share of lie trials answered correctly, including timeouts in the denominator.
- Higher means more answers followed the cue
- Accuracy%
- Share of all test trials answered according to the fact and cue.
- Read alongside response time
- Usable Truth Trialscount
- Correct truth-cue answers included in the time mean.
- Denominator for the mean
- Usable Lie Trialscount
- Correct lie-cue answers included in the time mean.
- Denominator for the mean
- Cue Switch Costms
- Mean correct time after a changed cue minus a repeated cue; first trials of blocks excluded.
- Secondary descriptive measure
- Responses Under 100 mscount
- Test responses faster than 100 ms.
- Excluded from response-time means
- Missed Answerscount
- Test trials without a valid F/J answer.
- Fewer means more questions answered
- Test Trialscount
- Test rows from the selected run.
- Completion context
- Planned Trialscount
- Number of test trials planned for the run.
- Setting context
- Practice Accuracy%
- Share of the four practice answers that followed the cue.
- Task understanding context
Use and evidence
6 papers from 2021 to 2025 name this task in their title or abstract, down 40% compared with 2016 to 2020. That ranks it 470 of 495 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 1 |
| 2024 | 0 |
| 2023 | 2 |
| 2022 | 0 |
| 2021 | 3 |
| 2020 | 1 |
| 2019 | 2 |
| 2018 | 2 |
| 2017 | 4 |
| 2016 | 1 |
| 2015 | 3 |
| 2014 | 2 |
| 2013 | 2 |
| 2012 | 4 |
| 2011 | 2 |
| 2010 | 2 |
| 2009 | 0 |
| 2008 | 0 |
| 2007 | 0 |
| 2006 | 0 |
| 2005 | 0 |
| 2004 | 0 |
| 2003 | 0 |
| 2002 | 0 |
| 2001 | 2 |
| 2000 | 0 |
Use grade E
Fewer than 30 papers from 2021 to 2025.
Evidence grade D
Little published measurement evidence found.
- Papers on test-retest reliability
- 0
- Papers on reliability or validity
- 7
- Registered clinical studies using it as an outcome
- 0
Note on the counts: Cued opposite answers only; detects nothing about truthfulness..
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 0.22.0, counted 2 November 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Questions
- 16 original harmless yes/no questions in each of eight languages: eight with Yes as the correct fact and eight with No.
- Trials
- 2 blocks of 32 trials by default, 1 to 3 as a setting. Each question appears once under each cue per block, in seeded order with no more than 3 identical cues in a row.
- Response
- A truth or lie cue appears for 500 ms before the question and stays visible. Press F for Yes and J for No, within 5,000 ms by default (2,000 to 8,000 ms). A 300 ms gap follows.
- Practice
- 4 separate questions with 1,000 ms feedback. Test trials have no feedback.
- Scores
- Lie cost: mean correct response time with a lie cue minus that with a truth cue. Answers under 100 ms and after the deadline leave the time means. Accuracy and usable counts accompany both conditions.
This is a cued response task using general facts. It detects nothing about a person’s truthfulness. The fact questions and mixed cues are our adaptation of instructed-deception research; compare results within the same language and settings.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: instructed_lying_test from the run with the most test rows; F for Yes and J for No. Correctness follows the fact and cue, with chance 50%. Below chance invalidates and not above chance is flagged. One key on 90% of answers invalidates when accuracy is not above chance. An unfinished run, fewer than eight usable responses in either condition, or fewer than three correct practice answers is flagged. Omissions and responses under 100 ms follow the timed-test rule.
Why these rules
Accuracy significantly below chance (one-sided exact test, p < .05) cannot come from guessing; it means the response mapping was reversed or the task was not followed (Slick, Sherman and Iverson 1999 treat below-chance forced-choice performance as definite response bias). Chance-level accuracy can be a real result in impaired participants, so it is only flagged. One option on at least 90% of answered trials, when the correct options are balanced and accuracy is not above chance, means the answers did not depend on the items (the task counterpart of long-string responding in surveys; Curran 2016). 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. The condition-count and practice limits are ConductScience choices.
No percentile. Scores and quality flags only.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Blocks | 2 | 1 to 3 |
| Answer time limit (ms) | 5,000 | 2,000 to 8,000 |
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.
- No percentile. Scores and quality flags only. How norms work
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite and describe
Participants completed the Instructed Lying Task in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Spence et al., 2001), with the standard settings (blocks: 2; answer time limit (ms): 5,000). The main score was lie cost (mean correct lie-cue time minus mean correct truth-cue time).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- Spence, S. A., Farrow, T. F. D., Herford, A. E., Wilkinson, I. D., Zheng, Y., & Woodruff, P. W. R. (2001). Behavioural and functional anatomical correlates of deception in humans. Neuroreport, 12(13), 2849-2853. https://doi.org/10.1097/00001756-200109170-00019Instructed truth and opposite answers; this version uses original general facts and records response time only.
Source papers
- Spence, S. A., Farrow, T. F. D., Herford, A. E., Wilkinson, I. D., Zheng, Y., & Woodruff, P. W. R. (2001). Behavioural and functional anatomical correlates of deception in humans. Neuroreport, 12(13), 2849-2853.Paradigm source, Adults
Questions
How long does the Instructed Lying Task take?
About 4 to 7 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?
Lie Cost, Truth Mean Response Time, Lie Mean Response Time, Truth Accuracy, Lie Accuracy, Accuracy, Usable Truth Trials, Usable Lie Trials, Cue Switch Cost, Responses Under 100 ms, Missed Answers, Test Trials, Planned Trials and Practice Accuracy. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Instructed Lying Task used in research?
6 papers from 2021 to 2025 name it in their title or abstract, down 40% compared with 2016 to 2020. That ranks it 470 of 495 test families in the ConductCognition test census (use grade E). Source: ConductCognition test census 0.22.0, counted 2 November 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Instructed Lying Task have?
In the published research, 0 papers report its test-retest reliability and 0 registered clinical studies use it as an outcome (evidence grade D in the ConductCognition test census).
Does it report a percentile?
No. Scores and quality flags only.
Which settings can a researcher change?
Blocks (1 to 3) and answer time limit (ms) (2,000 to 8,000). 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, with its words in the same language. 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.
Every test: the full test list.
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