How long does the Psychomotor Vigilance Task take?
About 4 to 6 minutes, as listed in the test library.
Attention
Psychomotor Vigilance Task
Track sustained attention, lapses, and fatigue-sensitive vigilance performance in the browser.
Useful for sleep, fatigue, operational-performance, and sedation-sensitive research settings.
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.
Attention4-6 minTimed: desktop or laptop with a mouse or trackpad
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What this task measures
Measures sustained attention by requiring rapid responses to infrequent visual targets over variable waiting intervals.
Core constructs
- Sustained attention
- Vigilance stability
- Fatigue sensitivity
- Alertness regulation
Research fit
- Sleep deprivation studies
- Fatigue monitoring in shift-work cohorts
- Medication sedation profiling
- Longitudinal attention stability tracking
Paradigm overview
The Psychomotor Vigilance Task (PVT) measures sustained attention by requiring immediate responses to infrequent visual targets after unpredictable waiting intervals. This structure minimizes strategic anticipation and isolates vigilance decline over time.
Unlike short burst reaction-time paradigms, PVT emphasizes attentional stability. A participant may begin with fast responses but accumulate lapses (very slow or missed responses) as fatigue, sleep pressure, or reduced alertness increases.
The PVT is widely used in sleep, fatigue, and operational-performance research because lapse counts and response variability are highly sensitive to vigilance impairment.
Key scoring outputs
Mean Reaction Time
msAverage valid response latency across scored trials.
Lower is better
Median Reaction Time
msMedian response latency, less influenced by outlier lapses.
Lower is better
RT Standard Deviation
msIntraindividual variability of response speed.
Lower is better
Lapses
countMissed responses or responses slower than the lapse threshold set for the study (500 ms standard).
Lower is better
False Starts
countAnticipatory responses under 100ms.
Lower is better
Response Rate
proportionProportion of trials with any response before timeout.
Higher is better
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Number of test trials | 40 | 20 to 80 |
| Lapse threshold (ms) | 500 | 300 to 1,000 |
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
- Task text: English and Italian.
- Available on: Every plan, including the free plan.
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite this test
Paradigm source: Dinges & Powell (1985).
ConductCognition versions: task version 1.0.0, scoring version 1.0.1. Every export records the versions each session used, for a methods section.
Source papers
No platform-matched normative source is currently seeded for this task in ConductCognition.
Paradigm sourceN/A
Research FAQ
Common questions about this online cognitive test
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?
Mean Reaction Time, Median Reaction Time, RT Standard Deviation, Lapses, False Starts and Response Rate. Each session is also marked valid, needs review or invalid, with the reason.
Which settings can a researcher change?
Number of test trials (20 to 80) and lapse threshold (ms) (300 to 1,000). Settings can be changed on yearly plans; free and pay-as-you-go studies use the standard settings.
Which languages can participants use?
The test's own text is in English and Italian. Italian participant pages come with yearly plans.
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.
Run this test in your next study
Start free with 10 free participants on any test, then use participant credits or a yearly plan.