Benefits of Sleep Extension on Performances During Total Sleep Deprivation (BankingSleep)
Condition: Sleep Deprivation
MeSH terms: Sleep Deprivation
Study type: Interventional

Summary: 
      Objectives: investigate the effects of 6 nights of sleep extension on physical and cognitive
      performances before, during total sleep deprivation (39 hours continuous awaking) and after a
      subsequent recovery sleep.

      Design: Subjects participated in two experimental conditions (randomized cross-over design):
      extended sleep (10-h in bed, EXT) and habitual sleep (8-h in bed, HAB). In each condition,
      subjects performed two consecutive phases: (1) six nights of either EXT or HAB (2) three
      experiments days in-laboratory:baseline (BASE), sleep deprivation (TSD) and after 10 h of
      recovery sleep(REC). Performance tests were administered every 3 hours over the 3-d in
      laboratory.

      Setting: This cross-over and randomized study was conducted under standardized laboratory
      conditions with continuous polysomnographic recording Participants: 14 healthy men (age
      range: 26-37 years) participated in the study.

      Interventions: EXT vs. HAB sleep durations prior to total sleep deprivation (39 hr continuous
      awaking).
    

Detailed description: 
      Many human endeavors require high-level cognitive performance situations (e.g., health care,
      military operations, space flight) along the whole nycthemera (i.e. the 24-h cycle).

      It has long been established that both acute total sleep deprivation (TSD) and chronic sleep
      restriction impair ability to maintain wakefulness, increase subjective sleepiness and sleep
      propensity, and most critically reduce various aspects of cognitive performance. In studies
      conducted in both laboratory setting and different professional situations inducing
      insufficient sleep, the most consistently and dramatically impacted cognitive capacities were
      sustained attention and alertness. This degradation of cognitive performance after a period
      of sleep deprivation is linked to an increase of sleep pressure, e.g. a reduction in the
      latency to sleep onset or increase of number of involuntary micro sleeps.

      To identify countermeasures to deleterious effects of sleep deprivation is critical in many
      professional areas.

      Management of wake/sleep cycle appears to have an important impact of alertness during sleep
      deprivation (e.g. sleep habits or physical activity, see the review. Recently, Rupp and coll.
      (2012) reported that one week of sleep extension realized before one week of sleep
      restriction (3 h/night) influence the rate of degradation of cognitive performance and
      alertness during this period and the subsequent recovery period. In other words, they
      proposed that sleep can be "banked" before a period of sleep loss and may help sustain
      performance and alertness. With a different experimental paradigm (i.e. without subsequent
      sleep deprivation), studies have shown that sleep extension (realized over different periods
      of time) may improve physical performance, attentional performance, or mood. The fact of
      increasing total sleep time over a period of time represents an attractive
      non-pharmacological countermeasure to limit the deleterious effects on performance induced by
      sleep privation. However, there is no study with cross-over and randomized design to assess
      effect on relatively short period (6 nights) of sleep extension on performance before, during
      total sleep deprivation and recovery. Moreover, there is no direct measurement of sleep
      pressure as continuous EEG monitoring to quantify micro sleep episode during period of sleep
      deprivation and effect of sleep extension on physical performance is not known.

      Hence, the aim of this study was to assess the effects of 6 nights of sleep extension (EXT)
      on physical and cognitive performances, alertness and homeostatic sleep pressure before,
      during total sleep deprivation and the subsequent recovery day.

      The investigators hypothesized that EXT would: i) partly prevents the physical and cognitive
      performances degradation-induced by total sleep deprivation ii) decreases the sleep pressure
      before, during and after total sleep deprivation and iii) improves the recovery speed of
      physical and cognitive performances.
    

Intervention name(s): Total Sleep deprivation
Intervention type(s): Other
Intervention description(s): Subject are submitted to 39 hours of continuous awaking in laboratory and a recovery night
Other intervention name(s): TSD
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: sleep extension; attention; physical performance