Spaceflight puts human into an extreme environment which has the specific and non-specifc factors like changes of circadian rhythms and interpersonal issues because of social isolation. Few studies investigated both the specific and non-specific factors of spaceflight on individual performance. Therefore, the present study used the sleep deprivation technique under social isolation environment to investigate its effects on individual cognition.
We compared the WM performances of 12 healthy males exposed to 72h social isolation and 72h sleep deprivation as separate conditions at four time points: one day before the experiment (pre-test), 12h and 36h into the experiment (test 1 and test 2) and one day after the experiment (post-test). A 2-back task and a resting state task were performed by the participants in the pre-test and post-test measurements, during which their galvanic skin response (GSR), heart rate (HR), and heart rate variability (HRV) were assessed.
Decrease of reaction accuracy (ACC) and increase of reaction time (RT) after 12h SD revealed WM impairments under social isolation environment. Compared to the pre-test, the participants’ GSR showed a significant decrease under both conditions. Compared to the resting state, the participants’ GSR, HR and HRV increased significantly during 2-back task under both conditions.
Results provided further evidence for impaired working memory after sleep deprivation. Our results elucidate part of the effects of sleep deprivation on the complex interactions between cognitive performance, behavior, and the autonomic nervous system under social isolation environment.