We are surrounded by a wide variety of sounds and noises every day. However, one sound is rarely heard, although it is particularly beneficial: the sound of silence. The absence of noise has a positive effect on our health, our cognition, and our well-being – in the long run, however, silence can also be harmful.
The importance of silence for our brain
Blood pressure, hormone release, sleep, and creativity: silence transforms our bodies, minds, and souls. Many studies look at the effect of silence on physical and mental health, and we should take heed of them. The more we know, the more we can benefit from silence.
The body relaxes
Silence has numerous positive effects on our body: For example, stress decreases significantly, which can be measured by the lower cortisol and adrenaline levels in the blood. A study from 2006 shows that just two minutes of silence reduces tension in the body and brain and is even more relaxing than music.
The blood circulation in the brain is regulated by silence just as general blood pressure; silence helps prevent heart attacks and strengthens the immune system. It not only influences the hormone release, as already mentioned, but also supports the cooperation of those systems that are controlled by hormones – such as the metabolism, the blood sugar level, the menstrual cycle, and the sex drive.
Besides, according to a study from 2015 , the active experience of silence has a positive effect on sleep behavior, especially among older adults. When we are awake, on the other hand, silence allows us to access the default mode network. These are the brain regions that are active while doing nothing and enable independent thinking, such as daydreaming.
According to a 2013 article in the Journal Brain Structure and Function, silence is, not least, doping for the brain. As part of a study, the team led by scientist Imke Kirste examined a group of mice and came to astonishing results: Two hours of silence create new cells in the hippocampus, the part of the brain in which learning processes, memories, and emotions are located. The new cells would be useless per se – but they have developed into functioning neurons that transmit impulses and information. Silence makes the brain grow!
Mind and soul thrive
Not only our bodies but also our minds and souls delight in silence. If we have the opportunity and allow ourselves to remain calm, we develop a deeper awareness of our environment and ourselves. Silence not only promotes introspection but also critical and sustainable reflection. We recognize coherences and find the strength to shape our lives – whether on an individual, professional, or even societal level.
Silence is also a real creativity booster, considered that it activates the DMN (default mode network) mentioned above. When we do nothing, we let our thoughts run free and find inspiration for novelty. We can now look at old problems from a different perspective and find innovative solutions. Also, we dare to think the unthinkable – and once a thought is conceived, it can become a reality.
The difficulty of finding silence in everyday life
At home the radio is on, the washing machine is spinning, and the refrigerator is whirring. Outside, cars are honking, only to be overruled by the jackhammer from the construction site, until finally a siren joins in. When we finally get to work, our colleague is already yelling on the phone while typing on his keypad. The background noise, especially in cities, does not seem to tolerate a break, and it is almost impossible to experience silence in everyday life. Yet, it is more than necessary to stay healthy and productive.
Workplace open-plan office
The connection between silence and health/performance particularly reveals itself in open-plan offices. These are becoming increasingly popular – unfortunately, at the expense of employees, as suggested by the results of a large-scale survey in the United States, Finland, Canada, and Australia. Scientists at the University of Sydney investigated factors such as air quality, privacy, lighting, and noise in open-plan offices. They found that employees are comparatively stressed and rather often need to take sick-leaves. In addition to the lack of privacy, it is above all the noise level that causes dissatisfaction. A research result by psychologist Matthew Davis confirms: Compared to employees who work in small or even individual offices, employees in open-plan offices are more stressed, significantly less concentrated and motivated. Therefore, it is no surprise that their productivity is suffering.
Noise contamination – a modern plague?
In 2011, the World Health Organization identified noise contamination as a “modern plague” and concluded that “there is overwhelming evidence that exposure to environmental noise has a negative impact on public health.”
But when does sound become noise? An irreversible hearing damage is caused at 80 decibels, hearing protection at the workplace is mandatory, starting from 85 decibels. But if you consider the maximum permissible continuous noise level emitted from construction sites – 55 decibels –, it quickly becomes clear: noise does not always have to be deafening. -so, even before our hearing gets permanently damaged, we suffer from noise emissions. Our body releases stress hormones, and our blood pressure rises. We become unfocused, even aggressive, which makes human interaction significantly more difficult. Other consequences are an increased risk of heart attack, strokes, and tinnitus. Concentration and performance suffer – especially in children, as a contribution to Psychological Science from 2002 shows.
Children suffer particularly from noise
Back then, a team of scientists examined the effect that the relocation of Munich Airport had on the health and cognitive performance of children. Six months before the relocation and 12 and 18 months afterward, the team conducted tests in reading, memory, attention, and listening for third- and fourth-graders who lived near the two airport locations and also went to school there.
The scientists found that the reading skills and long-term memory of those children living near the old airfield improved after the airport moved. However, the performance of those children near the new airfield declined. The researchers were also able to demonstrate that children who are exposed to long-term noise develop a stress response: they ignore the noise, but they also ignore relevant stimuli such as speech. Even though their hearing is not impaired, their inability to pick up speech remained after the noise had stopped.
Acoustic breaks can help
The good news is that we can counteract the adverse effects of noise on our cognitive performance, health, and well-being. We only have to actively seek distance and silence – in nature, for example, the sounds of which have a healing effect. But even if we live in a city and rarely have the opportunity for long walks or getaways, we can spare our ears by taking acoustic breaks. At home, for example, we can turn off the radio or television and enjoy the silence – for an extended period. Ten hours of rest is recommended. That sounds like a lot, but it is appropriate to avoid hearing damage – and it should not be too hard, given the fact we sleep between six and eight hours!
Learn to appreciate silence
Have we forgotten how to appreciate silence? It seems that way, if you look at the results of an experiment, the results of which were published in Science magazine in 2014: Volunteers were asked to stay alone in a room for between six and 15 minutes. They were only given a button – if they pressed it, they gave themselves a slight electric shock. 12 out of 18 men and 6 out of 24 women preferred to shock themselves rather than being alone with their thoughts. Many participants used the button more than once.
According to Timothy Wilson, one of the scientists behind the experiment, this behaviour is perfectly normal. The human brain is designed to connect to the outside world. Even if you want to concentrate entirely on yourself, the focus is mainly on the outside. However, there are techniques to control your thoughts – meditation, for example. Some people shy away from meditating because they believe that they must completely put their thoughts down. However, this is not entirely true: thoughts may well come, but you should also be able to let them go.
If this is still too difficult for you, start with simple exercises:
- For example, start your day with silence. Set your alarm clock ten minutes earlier and spend the additional time just with yourself.
- Another option is a walk in nature. Without any distraction of music played through your headphones.
- Breathing exercises are also a good idea and can prepare you for more intensive mediation practices.
Permanent silence harms the brain
All of the positive effects described become obsolete, and silence turns into a harmful factor, if we are exposed to it for too long. This is especially true for people affected by hearing loss. As Professor of Neurophysiology, Andrew King explains: When hearing loss occurs, the hair cells in the ear die first, at which point many of the nerve fibers that transmit sound signals from the ear to the brain degenerate. The auditory cortex in the brain will no longer receive auditory inputs and the longer the auditory center in the brain is not provided with sound, meaning the longer the duration of silence, the more the brain "forgets". It is, therefore, crucial to find appropriate treatment, for example through a cochlear implant, as soon as possible a hearing loss occurs, as this is the only way to ensure that the hearing is mostly preserved.