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Sleeping under the Ocean: Despite Total Isolation, Nuclear Submariners Maintain Their Sleep and Wake Patterns throughout Their Under Sea Mission.

Trousselard M, Leger D, van Beers P, Coste O, Vicard A, Pontis J, Crosnier SN, Chennaoui M - PLoS ONE (2015)

Bottom Line: PSG analyses showed that sleep did not significantly vary in length (total sleep time) or in quality between D21 and D51.Blood cortisol levels did not vary significantly.These results show that humans living in an isolated environment for more than two months with this specific shift schedule do not suffer from any significant effects on sleep, sleepiness and confusion between D21 and D51, when they follow an organized regular shift pattern with controlled light and temperature.

View Article: PubMed Central - PubMed

Affiliation: Institut de recherche biomédicale des armées (IRBA), Unité Stress, Brétigny-sur-Orge, France.

ABSTRACT

Background: To assess the effects of isolation, inadequate exposure to light and specific shift work on the subjective and objective measurements of sleep and alertness of submariners.

Purpose: A strictly controlled randomized crossover study with the polysomnography recorded twice during the mission.

Methods: Setting: Shift and night work with prolonged (70 days) social isolation from the real world (with no phone or Internet contact with families or friends during a routine mission aboard the "Téméraire" French Strategic Submarine with Ballistic Nuclear missiles (SSBN). Participants: 19 submariners working on a 24-hour shift for three days in a row schedule. Interventions: The participants attended two polysomnographic (PSG) recordings of night sleep on Day 21 (D21) and Day 51 (D51) of the 70-day patrol; urine cortisol levels were also taken after sleep, and subjective assessments of sleep, sleepiness, mood and anxiety on D21 and D51. The light and temperature on board were also recorded.

Results: PSG analyses showed that sleep did not significantly vary in length (total sleep time) or in quality between D21 and D51. The mariners reported the same subjective sleep, sleepiness, anxiety or mood (except for a slightly worse score for confusion on D51). Blood cortisol levels did not vary significantly.

Conclusions: These results show that humans living in an isolated environment for more than two months with this specific shift schedule do not suffer from any significant effects on sleep, sleepiness and confusion between D21 and D51, when they follow an organized regular shift pattern with controlled light and temperature.

No MeSH data available.


Related in: MedlinePlus

The top of the "Fig. 1" shows the 70-day long mission with the 3-day shift schedules to better understand at what point of the mission the polysomnography (PSG) recordings were performed.The submarine “Téméraire” is also shown schematically with the different levels of lighting in the “work”, “leisure” or “sleep” rooms. The graph at the bottom left of the "Fig. 1" shows the evolution of objective sleep parameters at the two points during the mission. Durations of TST (total sleep time), WASO (Wake after sleep onset), SWS (slow wave sleep), and REM (Rapid Eye movement) sleep did not vary significantly.
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pone.0126721.g001: The top of the "Fig. 1" shows the 70-day long mission with the 3-day shift schedules to better understand at what point of the mission the polysomnography (PSG) recordings were performed.The submarine “Téméraire” is also shown schematically with the different levels of lighting in the “work”, “leisure” or “sleep” rooms. The graph at the bottom left of the "Fig. 1" shows the evolution of objective sleep parameters at the two points during the mission. Durations of TST (total sleep time), WASO (Wake after sleep onset), SWS (slow wave sleep), and REM (Rapid Eye movement) sleep did not vary significantly.

Mentions: The study was performed during a 70-day mission on board the SSBN French submarine “Le Téméraire” in 2011. The environmental conditions inside the SSBN were strictly controlled "Fig 1".


Sleeping under the Ocean: Despite Total Isolation, Nuclear Submariners Maintain Their Sleep and Wake Patterns throughout Their Under Sea Mission.

Trousselard M, Leger D, van Beers P, Coste O, Vicard A, Pontis J, Crosnier SN, Chennaoui M - PLoS ONE (2015)

The top of the "Fig. 1" shows the 70-day long mission with the 3-day shift schedules to better understand at what point of the mission the polysomnography (PSG) recordings were performed.The submarine “Téméraire” is also shown schematically with the different levels of lighting in the “work”, “leisure” or “sleep” rooms. The graph at the bottom left of the "Fig. 1" shows the evolution of objective sleep parameters at the two points during the mission. Durations of TST (total sleep time), WASO (Wake after sleep onset), SWS (slow wave sleep), and REM (Rapid Eye movement) sleep did not vary significantly.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4446350&req=5

pone.0126721.g001: The top of the "Fig. 1" shows the 70-day long mission with the 3-day shift schedules to better understand at what point of the mission the polysomnography (PSG) recordings were performed.The submarine “Téméraire” is also shown schematically with the different levels of lighting in the “work”, “leisure” or “sleep” rooms. The graph at the bottom left of the "Fig. 1" shows the evolution of objective sleep parameters at the two points during the mission. Durations of TST (total sleep time), WASO (Wake after sleep onset), SWS (slow wave sleep), and REM (Rapid Eye movement) sleep did not vary significantly.
Mentions: The study was performed during a 70-day mission on board the SSBN French submarine “Le Téméraire” in 2011. The environmental conditions inside the SSBN were strictly controlled "Fig 1".

Bottom Line: PSG analyses showed that sleep did not significantly vary in length (total sleep time) or in quality between D21 and D51.Blood cortisol levels did not vary significantly.These results show that humans living in an isolated environment for more than two months with this specific shift schedule do not suffer from any significant effects on sleep, sleepiness and confusion between D21 and D51, when they follow an organized regular shift pattern with controlled light and temperature.

View Article: PubMed Central - PubMed

Affiliation: Institut de recherche biomédicale des armées (IRBA), Unité Stress, Brétigny-sur-Orge, France.

ABSTRACT

Background: To assess the effects of isolation, inadequate exposure to light and specific shift work on the subjective and objective measurements of sleep and alertness of submariners.

Purpose: A strictly controlled randomized crossover study with the polysomnography recorded twice during the mission.

Methods: Setting: Shift and night work with prolonged (70 days) social isolation from the real world (with no phone or Internet contact with families or friends during a routine mission aboard the "Téméraire" French Strategic Submarine with Ballistic Nuclear missiles (SSBN). Participants: 19 submariners working on a 24-hour shift for three days in a row schedule. Interventions: The participants attended two polysomnographic (PSG) recordings of night sleep on Day 21 (D21) and Day 51 (D51) of the 70-day patrol; urine cortisol levels were also taken after sleep, and subjective assessments of sleep, sleepiness, mood and anxiety on D21 and D51. The light and temperature on board were also recorded.

Results: PSG analyses showed that sleep did not significantly vary in length (total sleep time) or in quality between D21 and D51. The mariners reported the same subjective sleep, sleepiness, anxiety or mood (except for a slightly worse score for confusion on D51). Blood cortisol levels did not vary significantly.

Conclusions: These results show that humans living in an isolated environment for more than two months with this specific shift schedule do not suffer from any significant effects on sleep, sleepiness and confusion between D21 and D51, when they follow an organized regular shift pattern with controlled light and temperature.

No MeSH data available.


Related in: MedlinePlus