The ability to control action is crucial for adaptive responding, but may be compromised in
situations involving strong emotions (e.g., threat) or when people are deprived of resources
(e.g., sleep). As compromised action control can have large consequences in threatening
situations, for example when police officers face a potentially armed suspect, we
experimentally investigated how acute threat and partial sleep deprivation affect the ability to
control impulsive responses, in 52 healthy young adults performing a simulated shooting task.
The results showed that acute threat increased the tendency to act quickly (i.e., reduced
response times; Coef = 9.46, 95% CI [3.49, 15.29], p = .001) and impaired response inhibition
(i.e., increased stop signal reaction times; Coef = -4.91, 95% CI [-9.47, -0.44], p = .035). In
addition, three nights of partial sleep deprivation (five hours [n = 28] vs. eight hours [n = 24]
of sleep), led to a significant decrease in overall response accuracy (Coef = -0.22, 95% CI [-
0.40, -0.05], p = .025). Contrary to expectations, our results did not show increased threat
sensitivity in sleep-deprived individuals (all p > .13). Nevertheless, they may have important
implications for professionals who are required to maintain behavioral control under high
levels of threat and who experience disturbed sleep due to e.g. shift work, as both factors
negatively affected performance