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MOST days, I am drowning in noise. As a work-from-home mother, I am stuck in the middle of a busy household with two dogs, two teenagers and a husband who works from the next room. It’s a cacophony of Zoom calls, phone notifications, video games, music and barking, and that’s before my neighbour starts up his leaf blower.

Is it any wonder I long for some silence? The World Health Organization backs me up – it says that our world is too noisy and that this is harming our health. Of course, for centuries we have known the importance of quietness: in many religions, silence is promoted as a vital healing process. But my noisy surroundings got me wondering what benefits there are to seeking silence in the modern age.

These days, people go in search of quiet in all sorts of places. They join monasteries for a silent retreat or head to the hills for a weekend’s peace. There is even an increasing trend for spending time in sensory deprivation or flotation tanks – if you can afford it. Indeed, in his book Silence: In the age of noise, Norwegian explorer Erling Kagge calls silence “the new luxury”.

Figuring out what peace and quiet actually does for our mental and physical health is the ambition of a group of neuroscientists and health professionals who are beginning to unravel the benefits. By getting to grips with their research, I discover that a little silence may be vital to offset the detrimental effects of our noisy world. But just how much quiet do I need, and where should I get it?

First, it isn’t just loud in my house. Many of us are living in environments that are too noisy (see “Silence in the city“). We are finely attuned to noise, and for good reason. From an evolutionary perspective, sounds give us vital information, helping us to better navigate the world and avoid danger. To help ensure that loud or unexpected noises get the attention they deserve, our internal chemistry changes in response to them. Our blood pressure goes up, our muscles tense and our body releases stress hormones that prepare us for what is coming next. In the short term, this is a good thing. It helps us fight or fly. When we are exposed to excessive noise over the long term, however, those sustained physiological responses can lead to health problems, from anxiety and depression to cardiovascular disease.

Noise pollution

In 2018, the World Health Organization , and a concluded that noise was an ongoing and widespread problem in Europe, with at least 1 in 5 people consistently exposed to levels considered harmful to health.

The good news is that researchers are hard at work trying to find a solution. Alongside making our environments quieter, they are seeking to understand what aspects of silent experiences are most beneficial and how we can best achieve results (See “How to be silent“).

After my friend told me that a 1-hour float in a sensory deprivation tank gave her a new lease of life, I decided to begin with this. Flotation tanks have been around since the 1950s, when researchers Jay Shurley and John Lilly built the first of these environments to study how the human brain responds to a lack of external sensory input. The design of the tanks has since evolved, with higher ceilings and wider pools so people can get the benefits of a reduced sensory environment without feeling claustrophobic.

After stripping off and entering a small, enclosed pod filled with salty water, I find it is very quiet – but not silent. I am aware of the sound of my breathing.

The human ear is exquisitely sensitive to noise, says , a clinical neuropsychologist and director of the Float Clinic and Research Center at the Laureate Institute for Brain Research in Tulsa, Oklahoma. “In these tanks, some people can even hear the sound of their eyes blinking.”

But it is that ability to focus on your breath or heartbeat that helps people more easily reach a relaxed or meditative state, says Feinstein. Meditation has a whole host of known health benefits, including reducing stress, promoting a sense of greater well-being and offering relief from chronic pain and migraines.

Flotation therapy

To further explore the use of a flotation tank as a therapeutic tool, Feinstein and his colleagues recruited 50 people diagnosed with a wide variety of anxiety and stress-related conditions and had them answer questionnaires . The participants reported decreases in stress, muscle tension, pain and symptoms of depression after a single, 1-hour float. Post-float measures also showed a significant increase in feelings of relaxation along with overall well-being.

“People who are chronically anxious or depressed are always ruminating, cogitating over what is happening – but when they can focus on their breathing and heartbeat in a float environment, they find a lot of their anxious thoughts dissipate,” says Feinstein. “These positive effects can last up to 48 hours.”

Tal Dotan Ben-Soussan, director of the Research Institute for Neuroscience, Education and Didactics at the Patrizio Paoletti Foundation in Rome, Italy, says these findings aren’t surprising. Silence, both inside and outside a flotation tank, can help people more easily get into the kind of meditative state that can promote healing and well-being, she says. “When we find ways to be quiet, we are not only quiet in our environment, but quiet in our inner selves. This allows us to be more aware of what is happening around us and what the situation may require from us so we can provide [a more] adequate response.”

While research hints that silencing most forms of external sensation through flotation therapy can elicit short-term reductions in anxiety, depression and pain, less is known about what effects it can have on the brain. To investigate, Feinstein and his colleagues got 48 people to participate in either three 90-minute float sessions or three 90-minute periods of relaxing on a reclining chair, spread over a period of three weeks. Each participant had their brain scanned using functional magnetic resonance imaging at the beginning and end of the trial. Float sessions (DMN), a collection of brain regions that are active when the brain is at rest or not engaged in a particular task.

It might seem counter-intuitive that the areas normally more active when the brain is at rest decreased in activity in a float tank, but Feinstein has an explanation. The DMN is closely linked to our internal mind chatter, he says. These areas of the brain that come to life when the brain is at rest are involved in rumination, stress and anxiety.

In a float tank, these areas reduce in activity, suggesting that it is helping you to avoid this internal chatter. Similar decreases in DMN activity are often seen in altered states of consciousness and during psychedelic experiences, which have been linked to improvements in various mental health conditions, including alcohol misuse and obsessive-compulsive disorder. In contrast, excessive DMN activity is commonly linked with depression. Feinstein says it is an exciting finding, because float tanks seem to offer an easy way of “resetting” our nervous system to prevent it from getting out of balance.

Too quiet

When I booked my own float, I invited my husband, who declined, stating: “Isn’t that a form of torture?” Certainly, common wisdom would tell you that silence isn’t always golden. The earliest studies of sensory deprivation are rife with people who panicked and experienced hallucinations. “Some of the older sensory deprivation experiments basically mummified people,” says Feinstein. “The early tanks looked like coffins. Sometimes you wore helmets that had air tubes coming in and out of them. These set-ups would [upset] the average person, let alone someone who was dealing with anxiety.”

If you are thinking of using a modern flotation tank, you may experience altered perception, but this tends to involve benign visual auras or subtle humming sounds. “When you don’t have external sensory stimuli coming in, the brain tries to fill the void to make sense of this dark and silent world,” says Feinstein.

But what about other kinds of silence? Can they be overwhelming too? Certainly, it is known that the average person can’t stay in an anechoic chamber – designed to lock out all sound from the outside world – for more than 15 minutes without feeling very uncomfortable. Yet even sitting in a quiet environment can be difficult for some. In a famous series of studies in 2014, led by Timothy Wilson at the University of Virginia, researchers found that than sit quietly with their thoughts – suggesting people prefer some stimulation over being left in silence, even if that stimulation is negative.

However, when Eric Pfeifer, a psychotherapy researcher at the Catholic University of Applied Sciences Freiburg in Germany and his colleagues replicated those studies in 2019, they found . “The participants in our study thought it was great. They enjoyed being alone in a room without a mobile phone or laptop,” he says. Pfeifer believes it might be that today’s participants are more familiar with meditation, yoga and silent experiences, so appreciate the quiet more. Yet he concedes that there are some people who won’t benefit from silence, particularly those who are in a heightened state of stress.

“People in these states may not be able to relax or calm down in a silent condition,” he says. Professional guidance can help, he adds, allowing people to approach silence slowly so that they can gradually enjoy the benefits.

To date, there are no studies that can predict who will benefit most from silence. looking at traits like impulsivity or self-awareness reveal that these don’t seem to affect the ability of silence to improve mood and increase relaxation. Even if you are quite impulsive or have difficulty getting into a meditative state, people still report a positive experience. But when it comes to reaping the benefits, Ben-Soussan says one characteristic is key: you need to want to engage in the silent experience. “We see from animal models and human studies that volition and intentionality is important,” she says. “When people do not want silence, it can be very distressing.”

Five minutes’ peace

Although I did feel more relaxed after my float, I wondered whether it was necessary. Would other kinds of near-silence, like a walk up a hill or a moment’s peace in my bathroom, also boost my health? For that answer, I turned to Pfeifer and his colleagues, who have been studying different types of silence and their potential benefits. Pfeifer’s group with one another. The tests included up to 15 minutes of silence experienced alone, or in a group, inside and outside, with instruction or without, paired with occasional episodes of relaxing music or without.

All types of silence led to improved mood and increased relaxation in the majority of participants. But some were better than others. Periods of silence in a natural setting like a park, when combined with a therapist to guide them with intermittent relaxing music or meditation, offered the best results.

This suggests I may need to invest a bit of time and money into seeking the best kind of quiet. But Pfeifer is convinced that silence is more attainable in everyday life than people think. First, complete silence isn’t necessary. In a recent study by Pfeifer and his colleagues, participants reported when they sat quietly in an outdoor garden compared with a completely silent room. Meredith Berry at the University of Florida in Gainesville says that converging evidence shows we can benefit any time we quiet things down, whether it is through silence, meditation or a walk in the woods.

Second, Pfeifer says that we don’t need a lot of silence to gain benefits. His studies report improvements to relaxation and stress relief in sessions that last less than 10 minutes, so he believes that even a few minutes’ peace in a bathroom can be helpful in managing physiological responses to our noisy world.

“You don’t need to spend hours in silence to see benefits,” he says. “It is likely better to have more frequency of silence for a few minutes at a time than a longer period of silence only once a week. We are so overstimulated by sound that just finding those places in your daily life where you can find some silence and trying to emphasise those can make a big difference.”

He doesn’t have to tell me twice. Even though I probably can’t fit a regular float into my week, I can certainly find a few moments each day for more silence, even if it’s in the bathroom. It’s the kind of luxury that is worth the investment.

Silence in the city

It’s official. The world is getting louder. The World Health Organization says that people living in cities like Mumbai, New York, Paris, Tokyo and Buenos Aires are being exposed to far more than the recommended 40 decibels (dB) of noise at night.

. A quiet rural area tends to clock in at 30 dB, while restaurant conversation is 60 dB and a lawnmower is 90 dB. Anything louder than 85 dB for extended periods can cause permanent hearing loss. Over time, however, regular noise over 50 dB is linked to a multitude of health issues, ranging from sleep disturbance to problems learning and even cardiovascular disease. “There are no ‘earlids’ that can protect your brain from noise,” says , an acoustic consultant who has contributed to the British and international standards for noise.

Several cities are working to turn the volume down. In 2004, the office of the mayor of London published called Sounder City. The strategy highlighted issues surrounding both industrial and transport-related noise, and how to manage it. “London is a quieter city because of those efforts,” says Antonio. “By providing recommendations for quieter buses, reducing noise from roads and also controlling noise from aircraft, they were able to make the city quieter.”

Other cities are taking note – introducing noise-reducing road coatings, for instance, alongside greenery that muffles sound. Some solutions are more specific: Washington DC’s ban on petrol-powered leaf blowers came into effect this year, while San Francisco has instituted quiet hours, with excessive noise in residential areas. In New York City, .

Antonio says the covid-19 pandemic led to quieter streets, with some roads being handed over for use by pedestrians and restaurants. “People are seeing the benefits of these more quiet environments in their cities,” he says. “I expect we will see much more of this in the future.”

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