(NewsNation) — A new study has revealed that pink noise, a type of ambient sound often used to promote rest, may actually worsen sleep.
Researchers at the University of Pennsylvania conducted a seven-night sleep laboratory study and found that REM sleep decreased by an average of 19 minutes per night when participants were exposed to pink noise while sleeping. The study also showed that earplugs were more effective than pink noise at reducing the impacts of environmental noise on sleep.
“REM sleep is important for memory consolidation, emotional regulation and brain development, so our findings suggest that playing pink noise and other types of broadband noise during sleep could be harmful,” said study lead author Mathias Basner, MD, PhD, professor of Sleep and Chronobiology in Psychiatry.
“Especially for children whose brains are still developing and who spend much more time in REM sleep than adults,” Basner added.
The study was limited by a small sample size (25 participants), the seven-night duration, shifting sleep conditions and the unfamiliar laboratory setting.
“Additional research on optimal (broadband noise) color/level and long-term use is needed, especially in vulnerable populations,” according to the study.
What is pink noise?
Pink noise is a type of broadband noise: “A continuous sound that spans a wide range of frequencies and has a steady, static-like quality,” according to Science Daily. Broadband noise also includes white, brown, blue and other color noises.
Pink noise is a mixture of all the frequencies humans can hear, but with lower frequencies emphasized. It includes several naturally occurring sounds, such as rainfall, wind and rustling leaves.
White noise is a mixture of all the frequencies humans can hear at the same level. It includes humming sounds from fans, radiators and televisions.
