The white noise8 min read . Updated: 25 Nov 2016, 05:06 PM IST
Why we have begun replacing noise with noise to help us find silence
In the age of science, everything one does in one’s wakeful hours seems destined to harm one’s body, or harm the earth. When they discover time travel in the distant future, they will come back to get us for making the earth a cesspit with our littering, meat-loving ways. And you can’t even tell who ‘they’ will be: humans, robots or the things robots will create. Even if you manage to worry enough to keep your hands off any buttons that spell your imminent or future demise, bad news, the worrying will thicken and quicken your blood, and being awake will get you anyway.
Being awake is worry. Being asleep used to be peace. Then, worry got sleep too. Turns out, the way you sleep is vital to how you function. Look at a diagram of the perfect sleep position and contort your body to resemble it accurately; put on a wearable that will monitor every second of your sleep, timing your shifts from rapid-eye-movement (REM) sleep to non-REM sleep; check whether what you eat and your exercises are affecting your sleep. Once you have found the perfect time to go to sleep, always nod off at that time, regardless of where you are and what you are doing; but not before setting your phone to gently wake you up during the lightest cycle of your sleep. Sleep has become serious work.
“It is as important as exercise or nutrition is to health," says Prof. H.N. Mallick of the Indian Society for Sleep Research, department of physiology, All India Institute of Medical Sciences, Delhi, and the whole of the Internet echoes this concern. So, when a cure for insomnia and disturbed sleep announces itself, it is not surprising that people rush straight from the vegan, gluten-free, organic food café to queue up for this new panacea. Enter white noise, the 21st century’s lullaby.
The scientific definition of white noise is a signal that has all the frequencies of sound available in equal proportion. It is similar to the colour white, in which all the colours are present equally. White noise is a flat sound, without a pattern.
The concept of white noise was first used by engineers to test equipment, in particular audio equipment. But then doctors realized that it could be used to manipulate the way we hear.
What is silence? Many construe it as the absence of all noise, a cave shut off from all the elements, a hotel room with soundproof walls and a noiseless air conditioner. But our ears don’t always agree with our views on silence. When there is a complete absence of noise, many of us hear a ringing or buzzing sound. The condition is called tinnitus and it can keep us awake all night, which, as we have learnt, is as much of a slight to our bodies as drinking a few glasses of cola to wash down a Big Mac.
Medical researchers realized that white noise could suspend tinnitus. Then, in the 1970s, studies began to show that white noise helped in inducing sleep, particularly in infants, a godsend for beleaguered parents.
When we sleep, Prof. Mallick explains, our brains go through a phase called a spindle, which blocks out noise. But spindles only occur in the second phase of sleep. So you can still hear an annoying sound, such as the dripping of the tap or the person next to you snoring, when you’re falling asleep, and a sudden noise, such as a biker honking and screaming as he races by, might wake you up in other phases of sleep.
So the solution was to shut out noise with—another noise?
“I know this seems crazy," says Stéphane Pigeon, a signal processing engineer and sound designer based in Brussels, Belgium. “But white noise is such that after listening to it for a few minutes, your brain stops hearing it."
White noise, then, it seemed, was true silence. And silence is a commodity in great demand in a world where you have to worry about how you sleep. Now, most people were already hearing a bit of white noise while they slept—the humming of the fan, or the flow of wind outside their window. But it was not controllable, and not always enough to shut out other sounds. And so, commerce made some noise around the business of silence.
White-noise machines have been around since the 1960s—devices that play the monotonous sound of rain, or a waterfall, or static. But in the 2000s, the market for them expanded dramatically. Marpac, which made its first white-noise machine in 1962, now has nine different products on sale. And there are several other players. Realizing phones could be turned into white-noise generators, dozens of apps entered the space. Search for white noise on YouTube and you will find recordings of everything from a bamboo water fountain to an aeroplane engine.
It helps that several studies have also revealed the possibility that white noise can aid focus, calm stress and lubricate the creative process. It must also help that we have let media invade our brains so much. Perhaps the natural sound of leaves rustling is no longer enough to nullify the memory of the cacophony we have experienced while attached to our headphones all day. Another digital sound is needed.
Many today swear by white noise. The very sound of it, they say, sends a message to their brains that sleep is near. They are primed to relax when they hear it. Except, most sound machines nowadays don’t produce real white noise. What they actually produce is more like pink noise or Brown noise, which don’t have all frequencies at the same level, like white noise, but are still monotonous and therefore soothing.
What Pigeon is attempting to do is produce neither white, pink, nor Brown noise, but a completely customized noise that is perfectly suited to each user’s ear and the noise he wants to shut out. “It’s unfortunate," Pigeon says, “that while we have names for frequencies of light—colours—we don’t for frequencies of sound. So we can’t tell someone exactly what noise we want." The problem with current noise machines, he explains, is that because they don’t know what frequency of noise is disturbing you while you sleep, they can’t perfectly counteract it. Say you’re being disturbed by the neighbourhood soprano, doing arias in the middle of the night. You are being disturbed by a high-frequency sound, so you need another high-frequency sound to block it. But if your noise machine is playing Brown noise, which has lower frequencies, then you will need to turn the volume way up to make it effective. This could have an impact on your hearing in the long run. What Pigeon has done with his website Mynoise.net and app myNoise (only for iOS) is give you the means to customize the noise you hear. There are 10 channels that let you play around with frequencies till you arrive at a noise that you can listen to on a low volume and still shun other noises. On Mynoise.net, you can listen to a cat purr or a stream flow, but in the exact combination of frequencies you want. It’s like giving someone a palette of all the basic colours and letting them mix them till they arrive at the most soothing one.
Perhaps in the future we will be talking about how our favourite noise is a deep shade of purple. But even if you think white noise is just a placebo and people who really want to sleep soundly should simply stop worrying about how many likes their Facebook post has got, or drink a glass of wine, the possibilities that learning about what particular combinations of frequencies do to our brains are exciting. Just so long as we don’t start obsessing about whether we’re sleeping to the perfect noise and let worry thicken and quicken our blood.
The white-noise guide
White-noise machines and apps are all rather similar, but there are a few differentiators
Synthetic Noise vs Natural Noise
Some machines and apps produce a synthetic white noise, which is similar to the noise you hear when your television set loses signal. Some record natural sounds—rain, waterfalls, etc.—and then digitally master them to sound patternless.
Recorded vs Internal Noise
All white-noise apps, and most machines, play recorded white noise, but the Marpac Dohm-DS generates it itself, by pushing air through the machine. You can also pretty much make your own version of this device with a small fan and any cylindrical container.
Looped vs Continuous
The easiest way to create white noise is to record 15 or so seconds of a sound and then loop it. But the brain tends to detect this after a while, and once the brain realizes a sound is looped, the white noise stops having an effect. Some white noise apps and machines actually record several hours of a noise so they don’t have to loop it.
The sound of goosebumps
Videos that claim to produce a sensation called autonomous sensory meridian response, or ASMR, are as popular on YouTube as white-noise clips. Little is known about why ASMR is produced, or what exactly it is, but certain sounds, such as whispering, the tapping of fingernails on a wooden surface, or a pencil scratching against paper, when recorded in a way that accentuates them, have been found to give some people a tingling sensation. Some have described it as a “brain orgasm". It’s a warm feeling that tends to give you mild goosebumps and a gentle shiver down your spine.
People have claimed ASMR helps them do everything from fall asleep to concentrate. There seems to be a whole industry forming around it. One YouTube channel, GentleWhispering, managed by a Russian-American named Maria (who goes by one name), has more than 800,000 subscribers. Many of Maria’s videos involved role-play, a common feature of ASMR videos. She is your doctor, your hairdresser, or your masseuse, and she is speaking to you softly, emphasizing certain sounds. It doesn’t matter what she says, if you’re inclined to feel ASMR, her voice will trigger it.