A research group in the College of Engineering has discovered that exposure to pink noise may help people sleep better. Jue Zhang, an associate professor in the Department of Biomedical Engineering, and co-workers from the Academy for Advanced Interdisciplinary Studies and First Hospital at Peking University, demonstrate that steady pink noise has significant effect on reducing brain wave complexity and inducing more stable sleep time to improve sleep quality of individuals, in their paper published lately in Journal of Theoretical Biology.
You’ve probably never been jealous of an elephant, but you’re about to be. Elephants need only three to four hours of sleep per night in order to be their happy elephant selves during the day. So what’s Dumbo’s secret?
Deeper, more stable sleep—and new research may have found the secret to helping you achieve elephantine-levels of repose each night: Pink noise.
You’ve likely heard of “white noise,” says study author Jue Zhang, an associate professor at Peking University, which is produced when the sounds of different frequencies are combined. Pink noise, on the other hand, is a type of sound in which every octave carries the same power, or a perfectly consistent frequency, Zhang explains.
“Think of rain falling on pavement, or wind rustling the leaves on a tree,” It’s called pink noise because light with a similar power spectrum would appear pink, he says.
To see how pink noise would affect human sleepers, Zhang and his team recruited 50 people and exposed them to either pink noise or no noise during nighttime sleep and daytime naps while monitoring their brain activity. The results: An impressive 75 percent of study participants reported more restful sleep when exposed to pink noise. When it came to brain activity, the amount of “stable sleep”—the most restful kind—increased 23 percent among the nighttime sleepers exposed to pink noise, and more than 45 percent among nappers, says Zhang.
What’s going on here?
Sound plays a big role in brain activity and brain wave synchronization even while you’re sleeping, Zhang explains. The steady drone of pink noise slows and regulates your brain waves, which is a hallmark of super-restful sleep.
To experience the benefits of pink noise in your own bedroom, Zhang recommends fans or noisemakers that produce steady, uninterrupted sound or that imitates falling rain or wind. You could also download an application that will play pink noise through computer speakers or your cell phone, such as the Perfect Sleep application. Just don’t wear headphones, which can disrupt sleep, he says.
Reference: Junhong Zhou, Dongdong Liu, Xin Li, Jing Ma, Jue Zhang, Jing Fang, Pink noise: Effect on complexity synchronization of brain activity and sleep consolidation, Journal of Theoretical Biology, Volume 306, 7 August 2012, Pages 68-72