title: Experimental Sleep Restriction Facilitates Pain and Electrically Induced Cortical Responses.
abstract: OBJECTIVE
  Sleep restriction (SR) has been hypothesized to sensitize the pain system. The current study determined whether experimental sleep restriction had an effect on experimentally induced pain and pain-elicited electroencephalographic (EEG) responses.
  
  
  METHODS
  A paired crossover study.
  
  
  METHODS
  Pain testing was performed after 2 nights of 50% SR and after 2 nights with habitual sleep (HS).
  
  
  METHODS
  Laboratory experiment at research center.
  
  
  METHODS
  Self-reported healthy volunteers (n = 21, age range: 18-31 y).
  
  
  RESULTS
  Brief high-density electrical stimuli to the forearm skin produced pinprick-like pain. Subjective pain ratings increased after SR, but only in response to the highest stimulus intensity (P = 0.018). SR increased the magnitude of the pain-elicited EEG response analyzed in the time-frequency domain (P = 0.021). Habituation across blocks did not differ between HS and SR. Event-related desynchronization (ERD) was reduced after SR (P = 0.039). Pressure pain threshold of the trapezius muscle region also decreased after SR (P = 0.017).
  
  
  CONCLUSIONS
  Sleep restriction (SR) increased the sensitivity to pressure pain and to electrically induced pain of moderate, but not low, intensity. The increased electrical pain could not be explained by a difference in habituation. Increased response magnitude is possibly related to reduced processing within the somatosensory cortex after partial SR.
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.
authors.forename: Dagfinn
authors.initials: D
authors.lastname: Matre
authors.affiliation: Key Laboratory of Cognition and Personality (Ministry of Education) and School of Psychology, Southwest University, Chongqing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Hu
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.|Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.
authors.forename: Leif A
authors.initials: LA
authors.lastname: Viken
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.|Norwegian University of Life Sciences, Ås, Norway.
authors.forename: Ingri B
authors.initials: IB
authors.lastname: Hjelle
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.|Oslo University Hospital - Ullevål, Department of Neurology, Section for Clinical Neurophysiology, Norway.|Norwegian University of Life Sciences, Ås, Norway.
authors.forename: Monica
authors.initials: M
authors.lastname: Wigemyr
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.
authors.forename: Stein
authors.initials: S
authors.lastname: Knardahl
authors.affiliation: Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.|Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Sand
authors.affiliation: National Institute of Occupational Health, Department of Work Psychology and Physiology, Oslo, Norway.|Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.|Oslo University Hospital - Ullevål, Department of Neurology, Section for Clinical Neurophysiology, Norway.
authors.forename: Kristian Bernhard
authors.initials: KB
authors.lastname: Nilsen
mesh_terms: D000293:Adolescent; D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology*; D018592:Cross-Over Studies; D004569:Electroencephalography; D004597:Electroshock / Q000009:adverse effects*; D005260:Female; D006185:Habituation, Psychophysiologic; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D010146:Pain / Q000209:etiology / Q000503:physiopathology*; D010147:Pain Measurement; D017288:Pain Threshold; D011312:Pressure / Q000009:adverse effects; D057566:Self Report; D012867:Skin / Q000503:physiopathology; D012892:Sleep Deprivation / Q000503:physiopathology*; D013003:Somatosensory Cortex / Q000503:physiopathology; D055815:Young Adult
keywords: EEG; event-related desynchronization (ERD); event-related potential (ERP); pain; pressure pain threshold (PPT); time-frequency analysis