Combined Effects of Acute Sleep Restriction and Moderate Acceleration (+Gz) on Physiological and Behavioral Responses to High Mental Workload

Fighter pilots have to perform tasks requiring high mental workload during moderate-intensity acceleration phases (2 to 3G) that can last several minutes. When these accelerations are performed in the body axis (+Gz), they induce a redistribution of blood flow in the lower limbs associated with a decrease in cerebral blood flow, partially compensated by activation of the sympathetic nervous system (baroreflex). The main hypothesis is that the effects of these prolonged accelerations, even of moderate intensity (\<+4Gz), could impair pilots' ability to perform complex cognitive tasks, with potential consequences for flight safety and mission conduct. Moreover, flight missions are often performed after sleep debt, which is known to induce cardiovascular responses, sympathetic nervous system activation and impaired mental performance. The secondary hypothesis is that sleep debt (3h of time spent in bed) may increase the impairment of cognitive performance during prolonged acceleration.