Noise & Sleep Quality
topic
Noise produces sleep disruption at levels below those required for conscious arousal — with traffic noise, snoring, intermittent urban sounds, and even low-level continuous noise producing measurable increases in cortisol, heart rate, and micro-arousal frequency during sleep without the sleeper's awareness of being disturbed. The WHO identifies nighttime noise as a public health issue, with traffic noise above 40 dB at night associated with measurable cardiovascular and sleep health effects.
Role
Noise is one of the most pervasive and least-controlled environmental sleep disruptors — particularly in urban environments where nighttime sound levels routinely exceed thresholds known to impair sleep architecture. The majority of urban dwellers have adapted to their noise environment psychologically (they no longer consciously notice the trucks, trains, or passing cars) without any corresponding physiological adaptation — continuing to experience cortisol responses and micro-arousals with every noise event throughout the night. White noise, earplugs, and acoustic treatment represent simple interventions with measurable sleep quality benefits that most urban sleepers have never systematically tried.