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Updated: Jun 20, 2026
07:28
A Protocol of Manual Tests to Measure Sensation and Pain in Humans
Published on: December 19, 2016
Pain sensitivity in sleepy pain-free normals
Bantu Samridhi Chhangani1, Timothy A Roehrs, Erica J Harris
1Sleep Disorders & Research Center, Henry Ford Health System, Detroit, MI 48202, USA.
Sleep
|September 4, 2009
Summary
Sleepy individuals exhibit increased pain sensitivity (hyperalgesia) compared to non-sleepy individuals, even after adequate time in bed. This finding highlights a potential link between sleepiness and altered pain perception.
Area of Science:
- Pain research
- Sleep science
- Human physiology
Background:
- Previous research indicates experimental sleep restriction causes hyperalgesia in non-sleepy individuals.
- The relationship between natural sleepiness and pain sensitivity remains less understood.
Purpose of the Study:
- To investigate whether healthy, sleepy individuals experience hyperalgesia compared to their non-sleepy counterparts.
- To explore the link between subjective sleepiness and objective pain sensitivity.
Main Methods:
- A between-groups sleep laboratory study was conducted with 27 healthy participants (18-35 years).
- Participants were categorized into sleepy and non-sleepy groups using the Multiple Sleep Latency Test (MSLT).
- Pain sensitivity was assessed using finger withdrawal latencies to radiant heat after 8 hours time in bed.
Main Results:
- Sleepy participants remained sleepy and demonstrated increased pain sensitivity (quicker finger withdrawal) compared to non-sleepy participants.
- This heightened pain sensitivity was observed after a single night with 8 hours time in bed.
Conclusions:
- Healthy, sleepy individuals exhibit hyperalgesia relative to non-sleepy individuals.
- Sleepiness may be associated with an increased perception of pain.
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