How Do I Use the PVT-B/PVT to Track Mental Fatigue?
The PVT-B/PVT is most effectively used when the primary goal is to monitor mental fatigue.
The PVT-B and PVT (Psychomotor Vigilance Task) are tools used to assess mental fatigue and cognitive readiness by measuring reaction time and attention lapses. They are particularly valuable for detecting fatigue-related declines in focus and alertness. While both serve similar purposes, they differ slightly in interstimulus interval (ISI) and what qualifies as a lapse.
When to Use PVT-B/PVT
- Monitor Mental Fatigue: After high-cognitive-load or physical training sessions.
- Assess Readiness: Pre-session, to evaluate focus and detect early signs of fatigue.
PVT Example: Before and After Training
The video example below shows performance changes during a demanding session.
📍 At the Start (21:19) – Fresh & Focused
- Reaction Time: 356ms (quick responses).
- Accuracy: 100% (perfect focus).
- Variation: 13% (consistent performance).
- Lapses: 1 (minimal attention errors).
📍 At the End (22:30) – Mentally Fatigued
- Reaction Time: 372ms (slower responses).
- Accuracy: 100% (still perfect, but slowing down).
- Variation: 20% (less consistent reactions).
- Lapses: 4 (more frequent attention errors).
These results indicate increased fatigue. Ideally, scores should return to baseline before the next session. If pre-session values continue to worsen over the week, it may signal that the athlete needs additional recovery.
Why Track Over Time?
We recommend tracking over at least a month to establish a baseline and identify each athlete’s normal range. This helps inform adjustments to training loads and recovery needs.
PVT vs PVT-B: Key Differences
PVT-B is ideal for quick assessments with higher cognitive load, while the full PVT provides a more comprehensive view of sustained attention thanks to its longer duration.
Duration:
- PVT: Available in 5-minute or 10-minute versions.
- PVT-B: A shorter 3-minute test.
Lapse Threshold:
- PVT: Responses slower than 500ms are considered lapses.
- PVT-B: A stricter threshold—responses slower than 355ms are lapses.
Interstimulus Interval (ISI) – Delay Between Stimuli:
- PVT: Longer ISI, meaning more time between reaction prompts.
- PVT-B: Shorter ISI, leading to a faster-paced test.
What Is a Lapse?
Lapses are key indicators of mental fatigue in athletes. They represent moments when an athlete responds much slower than usual, often due to a lack of focus. When mental fatigue sets in, athletes tend to have slower reaction times, more variation in their responses, and a higher number of lapses. Therefore, tracking lapses helps measure mental fatigue. If the number of lapses increases, it’s a warning to pay closer attention to the athlete’s data.
Psychomotor Vigilance Test (PVT)
The psychomotor vigilance test assesses sustained attention and is currently the gold standard in fatigue detection.
🔗 Number of Lapses during the Psychomotor Vigilance Task as an Objective Measure of Fatigue