Pink is the new white – when it comes to noise at least.
Thanks to the wonders of YouTube, the static buzz reminiscent of old analogue TVs and humming fridges has been used for years as a tool for people with insomnia, new mothers lulling babies to sleep and workers with the Sunday night fear. Now though, there’s a new signal to tune into for ultimate relaxation.
In a sleep and memory study conducted by scientists at Northwestern University Feinberg School of Medicine in Chicago, participants were played pink noise – sounds similar to waves or a waterfall, rather than flat, constant white noise – over two nights in a sleep lab.
They found that those who had listened to pink noise before bed benefited from a deeper sleep and performed three times better on memory tests than on other nights.
What is pink noise?
Here comes the science (courtesy of livescience.com): White noise has an equal power per hertz through all frequencies, while in pink noise the power per hertz decreases as the frequency increases.
This means that the lower frequencies in pink noise are louder.
Ocean waves, waterfalls, heartbeats and even traffic are natural examples of pink noise. It’s recently been adopted in business settings to mask low-frequency background sound in a bid to “increase productivity and concentration” among workers.
Listen to the relaxing sounds for yourself:
“This is an innovative, simple and safe non-medication approach that may help improve brain health,” said senior author Professor Phyllis Zee.
The study, published in Frontiers in Human Neuroscience, involved 13 people between the ages of 60-84 – an age group highly susceptible to poor quality sleep and memory loss.
She added that pink noise is a potential tool for “enhancing memory in older populations and attenuating normal age-related memory decline”.
The results back earlier findings in China, when researchers at Peking University studied 40 sleepers and discovered pink noise resulted in “significant enhancement” in “stable sleep time”.
Previous research in young adults has also found that their memory improved at school after being played short, loud bursts of pink noise.
It’s worth noting that the pink noise played in the sleep studies was spaced out to sync with brain waves and prevent the brain from getting used to the noise and blocking it out – which is also where high-tech sound machines claim to help.