Does pink noise improve deep sleep?
MixedClaim: "Pink noise improves deep sleep and memory"
The nuance the wellness sites skip: the famous result used pink-noise pulses phase-locked to slow brain waves during sleep — not background pink noise on a loop. In 13 older adults that synced stimulation increased slow-wave activity and verbal recall (d = 0.63). But replication is inconsistent — a later study found no memory benefit — so treat it as a real lab effect, not a guaranteed one, and not the same thing as continuous pink noise from an app or speaker.
Sources
- Original study (phase-locked pink noise, n=13): Papalambros et al., Frontiers in Human Neuroscience (2017) 10.3389/fnhum.2017.00109
- Failed replication / null result: Schneider et al. (2020), discussed in Frontiers in Sleep meta-review (2023) 10.3389/frsle.2023.1294957