Psychomotor Vigilance Test (PVT)

Background

The Psychomotor Vigilance Test (PVT) is one one of the most widely used measures of behavioral alertness, tracking response times to unpredictable visual stimuli over a sustained period of time.

The Psychomotor Vigilance Test (PVT) was invented in 1985 by David Dinges and John Powell who developed the test as an objective, simple quantitative measure of vigilant attention under the influence of sleep deprivation. First termed a 'visual reaction time task', the task was later re-coined to 'the Psychomotor Vigilance Test' as sustained attention over time is a key element of the PVT.

The PVT has been shown time and time again to be a reliable, highly sensitive instrument to sleep deprivation.

Task Procedure

Participants are instructed to press the spacebar as soon as a red stopwatch stimulus appears on screen. Once pressed, the response time (in ms) is reported back to the participant. The red stimulus appears unpredictably every 2 to 10s and the task lasts (by default) 10 minutes. Participants work through a habituation phase of 1 minute before the test phase starts without further notice. Responses that are made too early are noted with an error message and a new trial is started.

What it Measures

The Psychomotor Vigilance Test (PVT) is a measure of behavioral alertness and sustained attention

Psychological domains

• Sustained Attention: Ability to quickly adapt one's thoughts and behavior to current demands

Main Performance Metrics

• Response Times: response times (in ms) to stimulus presentation
• Response Times Variability: response time variability across the task duration
• Number 0f Lapses: number of times a participant's response time exceeds 500ms

Psychiatric Conditions

PVT performance is affected in the following groups of people

• Narcolepsy
• Sleep Apnea
• Insomnia
• Sleep Deprivation