Efficacy of pink noise and earplugs for mitigating the effects of intermittent environmental noise exposure on sleep

Abstract

Study Objectives: Nighttime environmental noise (EN) exposure disturbs sleep and increases morbidity and mortality. Affordable and effective countermeasures are needed, but rigorous research is scarce. This study investigates the efficacy of pink noise (PN) and earplugs for mitigating the effects of intermittent EN on sleep. Methods: Twenty-five healthy adults (mean ± SD age 28.5 ± 5.9 years, seven male) participated in a seven-night polysomnographic laboratory study with different noise conditions including exposure to EN (93 events; maximum sound pressure level 45 to 65 dBA), PN (40 or 50 dBA), earplugs, and their combination. In the morning, participants completed cognitive tests, cardiovascular measurements, hearing tests, and surveys. Results: Compared to a noise-free control night, EN reduced N3 deep sleep (p < .0001) while PN reduced REM sleep (p