Sleep deprivation impairs affordance perception behavior during an action boundary accuracy assessment

Objectives Astronauts must adapt behaviors to changing affordances (action possibilities) when exposed to operational stressors such as sleep deprivation. The inability to correctly perceive affordances may cause astronauts to attempt behaviors that place them at greater risk. This study investigated the effects of sleep deprivation on affordance perception performance during 30-day NASA Human Exploration Research Analog missions. Methods Sixteen participants completed a perception-action coupling task (PACT) over days 22–25 of the missions. Participants completed sessions on day 22 (1800) and 24 (1200 and 1730) under normal sleep conditions and sessions on day 25 (0430, 1200 and 1445) after a night of sleep deprivation. During PACT, participants judge whether virtual balls afford posting (can fit) through virtual apertures. The ratio of ball-to-aperture size ranges from 0.2 to 1.8 (afforded trials <1, unafforded trials >1). A two-way repeated measures ANOVA was used to analyze the effect of time and trial type (afforded versus unafforded) on response time (RST) and accuracy (ACC). Results For RST, significant main effects of time (F2.666, 39.984 = 7.685, p = 0.001) and trial type (F1, 15 = 17.554, p = 0.001) were observed. Afforded RST was greater than unafforded RST. ACC decreased across time (F2.724, 20.939 = 5.137, p = 0.005) but did not differ between trial types. No significant interaction effects were observed. Conclusion Decrements in affordance-based behaviors were observed under increasing levels of sleep deprivation and subjects responded slower to trials where the task-specific affordance was available. These decrements may relate to changes in operational performance.