EEG Analysis for the Objective Assessment of Drowsiness

The objective of this clinical study is to develop solutions for the evaluation and management of drowsiness, based on 2 EEG sensors only, aiming at reducing the risk of accidents related to secondary hypersomnolence (sleepiness induced by sleep restriction or abnormal sleep/wake cycle). This project will allow a better understanding of the determinants of drowsiness and its impact on cognitive performance and the development of methods and models for the evaluation and prediction of cognitive performance deficit related to sleepiness. The secondary hypersomnolence will be objectified by continuous EEG recording and analysed by visual reading according to Objective Sleepiness Scale (OSS) criteria and automatically analyzed using the MEEGAWAKE algorithm (developed by PHYSIP). The level of secondary hypersomnolence will be modified by varying the duration and maintening of prior sleep or the sleep timing. The ability to stay awake will be measured by the maintenance of wakefulness test (MWT). Subjective sleepiness and mind wandering will be measured before and/or after all measurements. Simulated driving task, maintenance of wakefulness tests and several cognitive tasks to measure sustained attention, alertness, selective attention will be performed every 4 hours.

Chronotype and general tendency to daydream in daily life will be evaluated at the inclusion visit. Healthy volunteers will be placed in sleep deprivation patterns that will modify the level of secondary hypersomnolence. These patterns correspond to sleep deprivation caused by work schedules usually observed: shift work (SDP1) or night on-call (SDP2). shift work will be simulated by total sleep deprivation for 24 hours (comparable to the first day of a night worker) followed by early morning sleep, and an extended 17 hours wakefulness (comparable to second day of night shift). Secondary hypersomnolence will be assessed throughout prolonged awakenings (24 hours + 17 hours). The night on-call will be simulated by two half-hour awakenings during the nocturnal sleep. Hypersomnolence will be measured within 17 hours of wakefulness following this sleep fragmentation. The sleep history (quantity and quality of sleep) will be evaluated by actigraphy + ambulatory polysomnography (1 day before the experiment) and 2 polysomnographies in the laboratory during the experiment. Polysomnography recordings will be visually and automatically analyzed by the ASEEGA algorithm. Ambulatory recordings are automatically analyzed by ASEEGA. Throughout these sleep deprivation patterns, electrophysiological variables (EEG, EOG and EMG) will be continuously recorded in order to identify objective drowsiness states determined visually using the OSS or automatically by the MEEGAWAKE algorithm. Subjective sleepiness scale, Mind wandering scale, maintenance of wakefulness tests (MWT, electrophysiological test) and cognitive tests will be repeated, every 4hr, throughout the sleep deprivation patterns in order to determine abilities to stay awake, driving performance, sustained and selective attention, vigilance.

Eligibility Criteria:
Inclusion Criteria:

* BMI between 18 and 27,
* With a score on the PHQ-4 scale less than or equal to 2 for scores A (Anxiety) and D (Depression),
* Subjects with no complaints of excessive daytime sleepiness (total ESS score \<11),
* Non-professional drivers,
* Subjects who have held their driving license for at least one year,
* Subjects affiliated to a social security scheme,
* Subjects able to understand the study,
* Subjects available to come to the 3 visits required by the study,
* Free, informed and written consent signed

Exclusion Criteria:

* Pathologies that can induce excessive daytime sleepiness: untreated narcolepsy or idiopathic hypersomnia, untreated restless legs syndrome, untreated periodic leg movement syndrome,
* Chronic insomnia disorder,
* Excessive alcohol consumption (\> 2 glasses per day) during the last 6 months,
* Excessive consumption of coffee, tea or cola-type caffeinated beverages (\> 5 cups/day),
* Severe pathologies involving the vital prognosis in the short term,
* Uncontrolled endocrine pathologies (dysthyroidism, diabetes),
* All progressive cardiac pathologies, treated or untreated,
* All progressive neurological conditions treated or not (brain tumor, epilepsy, migraine, stroke, sclerosis, myoclonus, chorea, neuropathy, muscular dystrophies, myotonic dystrophy, etc.),
* Substance dependence,
* Shift workers or night workers who have performed on-call or on-call duty in the last 72 hours,
* Patients taking psychotropic drugs (antidepressants, antihistamines),
* Long-term treatment with benzodiazepines and z-drugs,
* Patients on cardiotropic,
* Deprived of liberty by a judicial or administrative decision,
* Pregnant or breastfeeding woman,
* Subject under legal protection (guardianship, wardship) or deprived from his rights following administrative or judicial decision