Whether it is nature sounds, the whine of a hairdryer or the incessant hum of a ceiling fan, white noise apps have been downloaded by millions of people around the world in the hope of getting a better night’s sleep. However, research suggests there is no good evidence that they work, and may even be making things worse.
True white noise is the hissy fizzing sound of all the frequencies that humans can hear being fired off randomly and at the same intensity. In recent years, numerous apps and devices have been developed that use it – or other “relaxing” sounds such as the hum of a fan or crashing waves – to help people fall asleep.
They have been hugely successful – the Bedtime Fan app, available on Apple devices, has had more than 3m downloads, while the Android White Noise Generator has more than 1m. One theory is that they help to drown out other bothersome sounds such as street noise; another is that listening to the same sound each night may trigger a kind of Pavlovian response, where people learn to associate it with falling asleep. But does it actually work?
Mathias Basner, a professor of […]