Absolute silence is not a biological necessity for good sleep, as our brain acts as an active acoustic filter inherited from our ancestors who slept in naturally collective and noisy environments.

noli's read

The idea that the brain actively filters sound stimuli rather than shutting down completely is scientifically accurate. Cognitive neuroscience studies confirm that the brain serves as a permanent sensory filter to identify potential warning signals during rest. From an evolutionary perspective, observational research conducted by anthropologists such as David Samson and Jerome Siegel among hunter-gatherer tribes (such as the Hadza) shows that ancestral sleep was indeed collective, adaptable, and far from silent. However, stating in a general way that our biology does not prefer silence for optimal recovery is an exaggeration. A major meta-analysis conducted for the WHO (Smith et al., 2022) robustly proves that uncontrolled nighttime noise fragments sleep and impairs recovery quality. In parallel, a systematic review (Capezuti et al., 2022) indicates that while stable sound stimuli (such as pink noise) can help with falling asleep by masking ambient noise, evidence for an overall improvement in sleep quality remains moderate. A quiet or acoustically neutral environment remains the safest option for the majority of people to maximize deep sleep.

the sources

1. 1Lan L, Tsuzuki K, Liu YF, Lian ZW. 2017
2. 2Brown TM et al. 2022