 "What is pink noise, believed to improve sleep?")
Pink noise is the new relaxation trend. It is a soothing alternative to white noise that promotes relaxation and improves sleep quality. There is growing interest in pink noise, brown noise, and green noise — a rainbow of soothing sounds — and their potential effects on sleep, concentration, and the relaxation response.
But do these colours actually help? What’s the science behind this?
What is pink noise?
The science is new, with only a few small studies to back it up, but that hasn’t stopped thousands of people from listening to hours of these noises on YouTube and meditation apps that offer a variety of colour noises with paid subscriptions.
To understand pink noise, start with white, the most familiar of the colour noises.
White noise is similar to static on a radio or TV. Sound engineers define it as having equal volume across all the frequencies audible to the human ear. It gets its name from white light, which contains all the visible colour wavelengths.
But the high frequencies of white noise can sound harsh. Pink noise turns down the volume on those higher frequencies, so it sounds lower in pitch and more like the natural sound of rain or the ocean.
Brown noise sounds even lower in pitch, giving it a pleasing, soothing rumble.
Pink and brown, like white, have standard definitions to audio experts. Other colour noises are more recent creations with very flexible definitions.
What’s the science behind colour noises?
White noise and pink noise may provide small benefits for people with attention-deficit/hyperactivity disorder, according to a recent review of limited ADHD studies. In theory, it wakes up the brain, said ADHD researcher and co-author Joel Nigg of Oregon Health & Science University in Portland.
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More Shorts“The noise provides stimulation to the brain without providing information, and so it doesn’t distract,” Nigg said.
White noise has been used to treat ringing or buzzing in the ear, called tinnitus.
Scientists at Northwestern University are studying how short pulses of pink noise can enhance the slow brain waves of deep sleep. In small studies, these pink-noise pulses have shown promise in improving memory and the relaxation response.
Pink noise has a frequency profile “very similar to the distribution of brain wave frequencies we see in slow-wave sleep because these are large, slow waves,” said Dr Roneil Malkani, associate professor of neurology at Northwestern University Feinberg School of Medicine.
If Northwestern’s research pans out, it could lead to a medical device to improve sleep or memory through personalised pulses of pink noise. But many scientific questions remain unanswered, Malkani said. “There’s still a lot of work we have to do.”
Is there any harm in trying colour noises?
If colour noises feel calming and help you drown out distractions, it makes sense to use them. Keep them at a quiet level, of course, to prevent hearing loss and take “plenty of breaks for the ears to rest,” Nigg said.
With inputs from AP
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