Timed pink noise increased brain fluid flow during sleep in a study
Researchers tested timed pink noise during sleep to see whether it could increase the flow of cerebrospinal fluid, or CSF, through the brain.
The study involved people sleeping in a magnetic resonance imaging machine while researchers monitored their brain waves.
The sound was played at peaks of slow brain waves, which are linked to CSF flow.
Brain scans showed more CSF flow during these periods than during control periods without noise.
The study did not show that more waste was cleared from the brain, and researchers do not yet know exactly why the sound affected fluid flow.
The brain’s glymphatic system moves CSF to help flush out waste, and disrupted sleep or aging may interfere with this process.
Researchers say future studies must test whether the method clears waste, including studies in animals and further work with people who are older or have sleep disorders.
Timed bursts of pink noise during sleep increased cerebrospinal fluid flow in a study published in Science Translational Medicine.
Researchers synchronized the sound with peaks in participants’ slow brain waves while they slept in an MRI machine.
Brain scans showed higher fluid flow during timed pink noise than during control periods with no sound.
The researchers have not established whether the increased flow cleared waste particles from the brain.
They say further research is needed, including studies involving older people and people with sleep disorders.
Who
Researchers led by Joshua Levitt, a biomedical engineer who recently completed his Ph.D. at Boston University, conducted the study.
What
Timed pink noise during sleep was associated with increased cerebrospinal fluid flow.
When
The study was published on November 9, 2026.
Where
Participants slept in a magnetic resonance imaging machine. The study’s location is not stated.
Why
The researchers aimed to test whether sound timed to slow brain waves could encourage cerebrospinal fluid flow.
This story does not have two clearly opposing sides.
Researchers timed pink noise bursts to participants’ slow-wave peaks while they slept in an MRI machine.
Brain scans showed higher cerebrospinal fluid flow during timed pink noise than during control periods.
The study was published in Science Translational Medicine.
Sound
Pink noise, with louder low pitches and quieter high ones
Timing
Noise was synchronized with peaks in slow brain waves
Comparison
Cerebrospinal fluid flow was higher during timed noise than during control periods
Lead author
Joshua Levitt, a biomedical engineer who recently completed his Ph.D. at Boston University
