Delta Waves and Cognitive Recovery

Study Overview
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Brief Summary
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In a laboratory protocol in healthy adults, exposed to a prolonged period of wakefulness with a restricted opportunity for sleep (40h of wakefulness / 3h of sleep / 21h of wakefulness), we hypothesize that the relative increase in spectral power of Delta waves [ 1 - 4 Hz] in NREM in the frontal territory, identified as a potential marker of the restorative function of sleep, during a night of sleep with limited recovery (3 h of time in bed) after sleep deprivation (40 h of continuous wakefulness), will be less important in subjects with poor recovery in terms of cognitive performance than in those with good recovery.

Detailed Description
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Exposure to sleep debt is one of the many stresses to which military personnel are exposed, during operational deployments or high-intensity training1. The kinetics of cognitive performance degradation during acute sleep restriction or deprivation are relatively well studied in the literature2, with significant inter-individual variability. Restoring these cognitive functions requires sufficient sleep, sometimes for several days. However, the military work environment often offers only limited opportunities for recovery, which does not allow for ad integrum restoration of cognitive capacities, although some subjects recover better than others. This is problematic in an environment where individual and collective performance levels are a prerequisite for safety and mission success3. In this context, early identification of poor recuperators, who do not sufficiently restore their cognitive performance after periods of rest, would enable us to adapt more effectively the use of different countermeasures (sleep extension, naps, adapted use of caffeine...)4. This implies the availability of validated objective markers, as subjective assessments are often inadequate in this context. The temporal data classically derived from the analysis of sleep macrostructure (total sleep time, duration of wakefulness after falling asleep, time spent in the various sleep stages, etc.) are compromised when the opportunity for sleep is restricted. It therefore becomes pertinent to look for non-temporal markers that would testify to the efficiency of sleep's recuperative function. Delta slow waves [1 - 4 Hz], which are mainly observed during deep slow-wave sleep on a sleep EEG, appear to be one of the indicators of the restorative function of sleep. They have been identified as a marker of sleep pressure5. The spectral power in this frequency range (delta power or slow-waves activity), obtained after fast Fourier transformation, bears witness to the activity of these waves. It is known to increase at the start of the night, particularly after sleep debt, and then gradually decrease, reflecting the dissipation of sleep pressure. It is recognized that high spectral power in this frequency range, particularly in deep slow wave sleep, is a marker of the depth of sleep6 . This depth could guarantee the restorative function of sleep. [...]

Official Title
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Delta Waves and Cognitive Recovery During a Restricted Sleep Opportunity After Total Sleep

Conditions
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Sleep Deprivation, Cognitive Impairment

Intervention / Treatment
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* Other: Sleep deprivatin
* Other: Sleep recovery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Healthy volunteer man or woman Between 18 and 45 years of age Having given written consent after having been informed of the terms of the study and the objectives of the genetic analysis performed Exclusion Criteria: Current medical treatment Chronic medical pathology, (psychol, cardiovascular or respiratory, sleep disorders) Pregnancy Sleep disorder Extreme chronotype Excessive daytime sleepiness Suspicion of anxiety or depressive disorder Estimated caffeine consumption > 200mg/d Not covered by a health insurance

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Intervention Model: Single Group Assignment
Interventional Model Description: Sleep deprivation followed by a short and a long recovery nigjht
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sleep<br>Sleep deprivation | Other: Sleep deprivatin<br>* 40 hours of continuous awakening<br>Other: Sleep recovery<br>* sleep recovery after 40 hours of continuous awakening<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Delta power | EEG Delta power in Hz | One night | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cognitive performance | Performance during PVT Test, in ms | 2 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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recovery, sleep