0203 Rise and shine! The efficacy of a multimodal environmental alarm system on mitigating the effects of sleep inertia

Abstract

Abstract Introduction Sleep inertia is a temporary period of reduced alertness and impaired physical and cognitive performance that immediately follows waking. Sleep inertia can have devastating consequences necessitating an intervention to successfully mitigate symptoms. Previous work has demonstrated modest benefits for individual environmental interventions which manipulate either lighting, sound, or temperature. The current study sought to expand on previous work and measure the impact of a multimodal intervention that collectively manipulated light, sound, and ambient temperature on vigilance, mood, and sleepiness. Methods 37 adults (M=27.13 years, 19 F) who self-reported taking longer than 30 minutes to wake up for 60% of their work week slept in the lab for four nights. They were woken up each morning with either a traditional alarm sound or the multimodal intervention (two control nights and two intervention nights, counterbalanced across participants). Feelings of sleep inertia were measured each morning through completion of the Psychomotor Vigilance Test and ratings of sleepiness and mood at five different time-points (5, 15, 30, 60, and 90 min after wake). Results While there was little impact of the intervention on all outcome measures, there were differential impacts depending on a person’s chronotype and the length of the lighting exposure during the intervention condition. Moderate evening-types who received a shorter lighting exposure (£15 min) demonstrated more vigilance lapses (p = 0.04) relative to the control condition whereas intermediate-types demonstrated better response speed (p < 0.005) and fewer lapses (p = 0.002). Conversely, moderate evening-types who experienced a longer light exposure (>15 min) during the intervention exhibited fewer false alarms over time (p = 0.03). Participants who received a longer light exposure also reported marginally lower negative affect the longer they were awake (p = 0.06). Conclusion Collectively, the results suggest that the length of the environmental intervention may play a role in mitigating feelings of sleep inertia, particularly for groups who may exhibit stronger feelings of sleep inertia including evening-types. Results may help inform the efficacy of “smart alarms” that activate based on entering light sleep. Future studies should measure this impact using additional measures of cognitive performance. Support (If Any)