Caffeine eliminates psychomotor vigilance deficits from sleep inertia.

Abstract

STUDY OBJECTIVES
This study sought to establish the effects of caffeine on sleep inertia, which is the ubiquitous phenomenon of cognitive performance impairment, grogginess and tendency to return to sleep immediately after awakening.
DESIGN
28 normal adult volunteers were administered sustained low-dose caffeine or placebo (randomized double-blind) during the last 66 hours of an 88-hour period of extended wakefulness that included seven 2-hour naps during which polysomnographical recordings were made. Every 2 hours of wakefulness, and immediately after abrupt awakening from the naps, psychomotor vigilance performance was tested.
SETTING
N/A.
PARTICIPANTS
N/A.
INTERVENTIONS
N/A.
MEASUREMENTS AND RESULTS
In the placebo condition, sleep inertia was manifested as significantly impaired psychomotor vigilance upon awakening from the naps. This impairment was absent in the caffeine condition. Caffeine had only modest effects on nap sleep.
CONCLUSIONS
Caffeine was efficacious in overcoming sleep inertia. This suggests a reason for the popularity of caffeine-containing beverages after awakening. Caffeine's main mechanism of action on the central nervous system is antagonism of adenosine receptors. Thus, increased adenosine in the brain upon awakening may be the cause of sleep inertia.

Authors

Van Dongen HP, Price NJ, Mullington JM, Szuba MP, Kapoor SC, Dinges DF

Source

MeSH

Adult
Arousal
Caffeine
Central Nervous System Stimulants
Circadian Rhythm
Double-Blind Method
Humans
Middle Aged
Polysomnography
Psychomotor Disorders
Reaction Time
Sleep Disorders
Sleep, REM
Wakefulness

Pub Type(s)

Clinical Trial
Journal Article
Randomized Controlled Trial
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

11683484