Preserving our natural soundscapes is crucial for our mental health and wellbeing

Dr Alison Greenwood

Chartered psychologist Dr Alison Greenwood, is alarmed by the potential impact on mental health of Heathrow’s proposed expansion.  National Nature Reserve, Richmond Park, a haven for over 5.5 million Londoners, will for the first time have low fight arrivals directly overhead and, says Dr Greenwood, “the loss of the peace and tranquillity in this much-loved natural space cannot be overstated”.

  • “There’s something about all those peaceful sounds in nature that really relaxes me”
    – an anxious 14-year-old in the lead up to her exams
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  • “When I’m outside in nature, it’s so serene and quiet, I feel all my anxieties slip away”
    – an Iranian man living in London, suffering from PTSD
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  • “When I stop to listen to nature’s sounds, and hear the birds singing and the wind in the trees, it really lifts my spirits, I feel connected, and I feel life might just be worth living again”
    – a disabled woman suffering from chronic depression

Most of us instinctively feel better when we spend time outside in natural environments. This is far from a new phenomenon: records dating back millennia reveal how early civilisations from all corners of the planet, Chinese Taoists, Ancient Egyptians, Australian Aborigines, valued the natural world for its therapeutic properties and in particular for its ability to soothe, heal, revitalise and rejuvenate.

Over the past forty years, researchers have applied scientific rigour to studying the mental health effects of spending time in tranquil natural environments, measuring blood pressure, heart rate, cortisol levels, skin conductance, and more recently, brain activity using MRI scans and EEG machines.  The conclusion of hundreds of scientific studies comprehensively demonstrates the mental health benefits of exposure to nature. This robust evidence shows that spending time in natural spaces can reduce depression, anxiety and stress, improve mood, sleep and cognitive functioning, and reduce symptoms associated with ADHD, trauma, psychosis, addiction, dementia and Alzheimer’s (references 1,2,3).

With approximately one in four people in the UK experiencing a mental health problem each year (4), and our NHS in crisis, thank goodness, then, for nature – a cheap, accessible, sustainable and effective resource, with the potential to combat a range of mental health symptoms and support the mental wellbeing of a nation.

With the World Health Organisation (WHO) asserting that mental disorders are now “among the leading causes of ill-health and disability” (3), governments around the world are beginning to recognise the huge part nature can play in supporting their population’s mental health, and are investing in their natural spaces accordingly. For example, the Japanese government sees nature as a central part of the national health care system, with 62 public ‘shinrin yoku’ (‘forest bathing’) nature trails specifically designed to treat stress, anxiety and depression, and a commitment to increasing the number to 100 within the next ten years to ensure every Japanese citizen has access to peaceful, unspoilt nature (1, 5).

Across Scandinavia self-guided nature walks, digital detox trails, and a wide range of nature-based interventions are generously funded by governments, both to treat mental health problems and to support wellbeing. The US are also investing heavily in green spaces, with a National Parks Prescription Programme and a growing number of projects using natural spaces to treat people with specific diagnoses such as PTSD, addiction, ADHD and autism.

And so to the UK.  With over 91% of us living in urban environments, and studies showing a significant increase in anxiety and mood disorders amongst city dwellers, one might expect our own Government to be doing all it could to protect our valuable natural spaces, and particularly those in and around cites. The UK Government clearly recognises the importance of natural spaces for mental health, asserting in its recently published ‘25 Year Environment Plan’ (2018) (6).

“Spending time in the natural environment – as a resident or visitor – improves our mental health and feelings of wellbeing. It can reduce stress, fatigue, anxiety and depression.”

It seems irrational then that the government is allowing Heathrow, as part of its plans for the third runway, to propose routing, for the first time, 47 low-flying arrivals as well as between 17 and 47 extra departures every hour directly over Richmond Park, London’s largest open space, a National Nature Reserve and Site of Special Scientific Interest and a unique place for wildlife.  Described by Sir David Attenborough in a recent film as the “quietest place in London”, and currently providing respite, rejuvenation and mental restoration to five and a half million visitors every year, the impact of the loss of the peace and tranquillity in this much-loved natural space cannot be overstated.

The potential negative effects of increased noise pollution from low-flying aircraft on mental wellbeing are of great concern. According to WHO, environmental noise features “among the top environmental risks to physical and mental health and well-being”, and in its recent ‘Environmental Noise Guidelines’ (2018), it strongly recommends reducing noise levels produced by aircraft to below 45dB, since “aircraft noise above this level is associated with adverse health effects” (7).  The current proposal of up to 47 new fight arrivals over Richmond Park as low as 2,000 f will produce noise levels up to 80dB, which is nearly eight times the WHO’s recommended maximum.

Numerous studies have demonstrated the links between noise pollution and stress.  In a sample of nearly a million people living near Bonn airport, women exposed to noise over 46dB were twice as likely to be on medication for hypertension as those exposed to noise under 46dB (8).  An extensive study of several thousand school children in the UK, Spain and the Netherlands living near large airports, showed significant impacts of noise levels in reading comprehension, memory and hyperactivity (9); and a study before and after the opening of the international airport in Munich showed a nearly doubling of stress hormones in children near the airport after fights began (10).

In addition to the harmful effects on mental health of noise pollution, the specific healing qualities of nature’s sounds will be lost under the unremitting roar of aircraft engines. A comprehensive Swedish study confirms that “good soundscape quality in natural spaces can only be achieved if the traffic noise exposure in suburban green areas and city parks during day time is below 50dB” (11).

The sounds of nature, the twitter of birds, the rustle of trees, the burble of flowing water, are especially beneficial to our mental wellbeing, with a number of studies demonstrating reductions in several indicators of stress (e.g. reduced cortisol levels, blood pressure and heart-rate) when participants are exposed to these natural sounds (12,13,14). Birdsong, in particular, has been found to have a significant positive impact on the human brain, and studies have shown improvements in mood and mental alertness whilst listening to the chatter of birds (15). Scientists have suggested that we find birdsong relaxing and reassuring because over thousands of years we have learnt that when the birds sing we are safe. Joshua Smyth, a bio behavioural health psychologist at Pennsylvania State University, who has been researching natural soundscapes for several years, concludes, “We should think about soundscapes as medicine. It’s like a pill…an acute stress intervention” (5).

The science then is unequivocal: natural spaces are a precious resource in addressing our current mental health crisis; noise pollution has a significant negative impact on our mental health; and noise pollution that destroys the restorative properties of our natural spaces is clearly damaging on both fronts.

However, as I reflect on the impact of Heathrow’s proposed expansion, I return to my personal experience of Richmond Park and those of my clients with which I began. I work as a psychologist offering ‘Nature Prescriptions’ to individuals with a range of mental health issues who are referred to our charity by their GPs. I regularly walk or sit in Richmond Park with people suffering from all kinds of mental distress, and I see first-hand the powerful healing qualities of being in such a magnificent natural setting (so rare in London), with clients visibly relaxing, smiling, and expressing a sense of freedom, release, connection, optimism and meaning. And when I ask my clients to describe what it is they most appreciate about spending time in the Park, adjectives such as “tranquil”, “quiet”, and “peaceful” are amongst the most frequently used, and the sounds of nature, the birds singing, trees rustling, and insects humming, are often cited ahead of nature’s sights and scents.

Our natural soundscapes then, such as we currently enjoy in Richmond Park, are not just a pleasant addition to a natural space, they are quite simply essential to our mental health and wellbeing and we should do everything in our power to preserve them.

Dr Alison Greenwood is a chartered psychologist who runs a mental health charity in South West London, Dose of Nature, established to promote the mental health benefits of engaging with the natural world. If you would like to know more about the charity, please contact her on agreenwood@doseofnature.org.uk

Press Release – Heathrow flight paths – impact on mental health, FINAL

 

References

  1. Song, C., Ikei, H., & Miyazaki, Y. (2016). Physiological effects of Nature Therapy: A review of the research in Japan. International Journal of Environmental Research and Public Health, 13(8), 781.
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  2. Van den Bosch, M., & Ode Sang, Å (2017). Urban natural environments as nature-based solutions for improved public health. – A systematic review of reviews. Environ. Res. 158 (Suppl. C), 373–384.
  1. World Health Organization (WHO) Report (2016). Urban green spaces and health. Copenhagen: WHO Regional Office for Europe.
  1. McManus S, Bebbington P, Jenkins R, Brugha T. (eds.) (2016). Mental health and wellbeing in England: Adult psychiatric morbidity survey 2014. Leeds: NHS digital.
  1. Williams, F. (2018). The Nature Fix. New York: W.W. Norton & Company.
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  2. DEFRA (2018). 25 Year Environment Plan. Retrieved from http://www.gov.uk/government/publications.
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  3. World Health Organisation (2018). Environmental Noise Guidelines for the European Region.
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  4.  Kaltenbach, M., Maschke, C., & Klinke, R. (2008). Health consequences of aircraft noise. Deutsches Ärzteblat Internatonal, 105(31-32), 548-556.
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  5. Clark, C., Martin, R., van Kempen, E., Alfred, T., Head, J., Davies, H. W., Haines, M., M. Barrio, I., L Matheson, M., & Stansfield, S. A. (2005). Exposure-effect relations between aircraft and road traffic noise exposure at school and reading comprehension: The ranch project. American Journal of Epidemiology, 163(1), 27-37.
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  6. Evans, G. W., Bullinger, M., & Hygge, S. (1998). Chronic noise exposure and physiological response: A prospective study of children living under environmental stress. Psychological Science, 9(1), 75–77.
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  7. Nilsson, M., & Berglund, B. (2006). Soundscape quality in suburban green areas and city parks. Acta Acustca United with Acustca, 92(6), 903-911.
  1. Alvarsson, J., Wiens, S., & Nilsson, M. (2010). Stress recovery during exposure to nature sound and environmental noise. Internatonal Journal of Environmental Research and Public Health, 7, 1036-46.
  1. Benfield, J., Taf, B., Newman. P., Smyth, J. (2014). Natural sound facilitates mood recovery. Ecopsychology, 6(3), 183-188.
  1. Gould van Praag, C., Garfnkel, S., Sparasci, O., Mees, A., Philippides, A., Ware, M., Otaviani, C., & Critchley, H. (2017). Mind-wandering and alterations to default mode network connectivity when listening to naturalistic versus artificial sounds. Scientific Reports, 7.
  1. Ratclife, E., Gatersleben, B. & Sowden, P.T. (2013). Bird sounds and their contributions to perceived attention restoration and stress recovery. Journal of Environmental Psychology, 36, 221-228.