Tired and wired: sleep deprivation prevents emotional adaptation to prolonged and ambiguous threat
Sleep problems are strongly linked to anxiety, but the psychological mechanisms underpinning this relationship are poorly understood. In this pre-registered study, we combined virtual reality, psychophysiology and multidimensional experience sampling to test the hypothesis that sleep deprivation disrupts emotional adaptation to sustained or resolving threat, giving rise to a heightened state of anxiety. Following a night of restful sleep or total sleep deprivation, healthy young adults navigated an immersive virtual world that alternated between ambiguously threatening and non-threatening contexts. Despite initial increases in emotional arousal, sleep-rested individuals quickly downregulated affective responses to ambiguous threat, reflecting efficient adaptation to the aversive virtual environment. Sleep-deprived individuals, by contrast, were unable to overturn elevated arousal responses, and exhibited a breakdown of goal-orientated, emotional control. Interestingly, resting heart rate variability, an index of affective regulatory capacity, mitigated arousal responses to ambiguous threat after sleep deprivation. These findings suggest that impaired adaptation to prolonged threat may represent a key mechanistic pathway linking insufficient sleep to anxiety.