Claim reviewed: Listening to continuous pink noise through the night strengthens deep sleep and memory.
What do we know?
A meta-analysis of studies using short acoustic stimuli timed to brain waves in deep sleep (closed loop, with EEG) found a small, trend-level effect on memory consolidation (g = 0.25, p = 0.07).
What don't we know?
This app does not use EEG; continuous (open-loop) pink noise is a different method. In a 72-person study, overnight pink noise did not increase insight and shortened the first light-sleep period after sleep onset. The authors say the evidence is insufficient to recommend commercial devices.
Wording we use in the app: Pink noise can be used to mask surrounding sounds during sleep; it has not been shown to lengthen deep sleep.
Sources (2)
Wunderlin ve ark. 2021 · Meta-analysis · 10 studies · 177 participants
A meta-analysis of 10 studies (177 participants) of short acoustic stimuli timed to slow waves during deep sleep and overnight episodic memory: the combined effect was small and at trend level, significant in phase-locked subgroups. The authors say the evidence is not sufficient to recommend commercial devices.
g = 0.25 (p = 0.07)
Wunderlin M, Züst MA, Hertenstein E, Fehér KD, Schneider CL, Klöppel S, Nissen C. Modulating overnight memory consolidation by acoustic stimulation during slow-wave sleep: a systematic review and meta-analysis. Sleep. 2021;44(7):zsaa296. doi:10.1093/sleep/zsaa296 PMID 33406249 Go to source
Vickrey ve Lerner 2023 · Experiment · 72 participants
In 72 participants, continuous (open-loop) pink noise during sleep did not increase insight compared with silent sleep; results were closer to the wake group. Pink noise shortened the first light-sleep (N1) period just after sleep onset.
Vickrey B, Lerner I. Overnight exposure to pink noise could jeopardize sleep-dependent insight and pattern detection. Front Hum Neurosci. 2023;17:1302836. doi:10.3389/fnhum.2023.1302836 PMID 38107593 Go to source
Last reviewed: 3 October 2026 · Next review: 3 April 2027