Effects of 72 h-isolation and confinement with sleep deprivation on astronaut's attention on network functions and operation performance of manual controlled simulated rendezvous and docking task

Objective To measure the effects of 72 h-isolation and confinement (IC) with or without sleep deprivation (SD) on attention network functions and operation performance of manual controlled rendezvous and docking task. Methods Twelve healthy male volunteers were randomly divided into 4 groups of 3. The experiments were done by means of self-control and cross-over design. Two groups underwent 72 h IC without SD, and then recovered for 7 d. After that, they underwent 72 h IC with SD. Other 2 groups underwent the identical environments in the opposite order. The evaluation of attention network functions and the functional nuclear magnetic resonance examination of brain were conducted before and after isolation. The operation performance of manual controlled rendezvous and docking task was tested during isolation. Meanwhile, the functional magnetic resonance imaging (fMRI) technology was used to evaluate the autonomic activity in the brain region. Results ①The volunteers, average reaction time, accuracy and omission rates of the attention network function test in 72 h IC had insignificant differences as compared with those before the isolation (P>0.05). The 72 h IC and SD caused average reaction time and omission rate evidently increased (t=2.505, 2.324, P 0.05). ②The fMRI data indicated that the spontaneous nervous activity in right frontal eye field was significantly weakened by IC and SD (t=6.580, P<0.05), but the activities in 3 clustering fields of right temporal lobe joint were significantly enhanced (t=6.726, 4.905, 8.305, P<0.05). ③As compared with those in IC condition, the volunteers, success rate of manual controlled rendezvous and docking task in IC plus SD condition was evidently decreased (χ2=9.761, P<0.01), but the fuel consumption, pitch angle deviation and yaw angle deviation were significantly increased (t=3.475, 3.161, 3.375, P<0.01) and the docking time was significant shortened (t=2.681, P<0.01). Conclusions 72 h IC and SD has negative effects on attention network function and operation performance of manual controlled rendezvous and docking task. Sleep deprivation would be the main factor. Key words: Sleep deprivation; Social isolation; Attention; Computer simulation; Aerospace medicine; Magnetic resonance imaging; Manual controlled rendezvous and docking