A synthesis of health benefits of natural sounds and their distribution in national parks.
Author: Emma Crumpton
About the Author: Emma Crumpton is a fourth year student at Northwestern University studying music cognition with interests in ecology and sexuality studies. She is passionate about music and art therapies education and research. While finishing up her degree at Northwestern, she enjoys hiking, gardening, indoor plant collecting, reading, and painting.
Soundscapes Without Noise – An Elusive Health Benefit
The true sounds of nature can positively influence health outcomes, but when those sounds are diluted with human-generated noise, the benefits are decreased, according to a recent study.
The study, "A synthesis of health benefits of natural sounds and their distribution in national parks," by R.T. Buxton, A. L. Pearson, C. Allou, K. Fristrup and G. Wittemyer, focused on nature’s sounds and soundscapes, their possible health benefits, and their distribution across U.S. national parks.
A soundscape is the collection of sounds perceived in an environment. There are biological sounds like the birds chirping, geophysical sounds like rain falling, and anthropogenic sounds like human voices and road traffic – these last often classified as “noise,” the unwanted sound in natural environments.
Published in March of 2021 the article offers a systematic study of previous literature to look for evidence of benefits of natural soundscapes and to determine to what degree, if any, soundscapes influence health outcomes. It also looks at the distribution of restorative sound environments.
The Buxton team found 36 useful studies, 18 of which they used for a meta-analysis – an examination of data from multiple studies to determine overall trends, of the results.
The results from the literature review showed a 184% overall improvement of health and positive affect in groups exposed to natural sounds, relative to comparison groups. Natural sounds on their own, without other sensory stimuli, can have positive health benefits, such as decreased pain, lowered stress, improved mood, and enhanced cognitive performance.
Water noises were most linked with improvement in health and positive affect, in those exposed to natural sounds, and bird calls were the biggest link to decreased stress and annoyance.
The study then looked at the NSNSD Acoustic Dataset, a data set created by the National Park Service Natural Sounds and Night Skies Division, which has been monitoring acoustic environments since 2000, listening to and observing spectrograms of recordings at 221 sites in 68 parks. These data were used to quantify the distribution of natural sounds and noise across U.S. national parks, considering location and visitation numbers.\
Of the 221 acoustic monitoring sites analyzed, 75.1% had high audibility of biological sounds and 40.7% had high audibility of geophysical sounds. Bird sounds were audible 42.1% of the time among sites and water-related sounds were audible 22.8% of the time among sites.
Overall, only 11.3% of sites had low audibility of anthropogenic sound and high audibility of biological or geophysical sounds, and 22.6% of sites had moderate audibility of noise and high audibility of biological or geophysical sounds. Such sites with restorative soundscapes may represent important acoustic environments for human health. They also may indicate that restoring soundscapes and eliminating noise could help bolster the potential benefits of these and other sound environments. Yet, accessibility is a factor, as only three sites with high audibility of biological or geophysical sounds and low anthropogenic sound audibility were within 100 km of urban areas, these included parks in Alaska, Hawaii, and the Pacific Northwest.
Because noise is an increasing problem in natural spaces, where it can disrupt the everyday functioning of environments and cause health-related problems in people, especially those living in high-noise areas like large cities, these results can inform planning to manage, conserve, and implement activities with natural
soundscapes to enhance human health, like guided soundwalks on nature trails.
Natural soundscapes can be thought of as resources to be protected and enhanced for ecological and human health benefits, such as preserving connections with nature, bolstering biodiversity conservation, and improving
Citation: "A synthesis of health benefits of natural sounds and their distribution in
national parks." Buxton, R. T., A. L. Pearson, C. Allou, K. Fristrup and G. Wittemyer
Author: Olivia Poole
About the Author: Olivia Poole is a third year at Northwestern University studying social/environmental policy and data science. She is passionate about using environmental policy and science to narrow healthcare disparities, and also very interested in urban agriculture and food sovereignty.
Research shows a vacant lot is not empty – it holds health risks and benefits.
Published in April 2021, this article aimed to answer the research question: How do poor quality greenspaces (e.g. vacant lots) influence health? While there are some limiting factors to this study and review, they point to opportunities for more research in this field.
After conducting a systematic review, the researchers consolidated the current literature about the effects of vacant lots on human health to summarize findings and identify gaps in the existing body of evidence to suggest future research.
Using PRISMA guidelines – the global standard for systematic and scoping literature reviews – the researchers found 438 articles, which were winnowed to 22; 11 used controlled experimental designs.
The researchers broke down the results from the selected articles into several categories but did not use a specific coding mechanism/scheme/framework at this point. Subsequently, they split the results into two categories of investigation: health outcomes (like stress) and health risks (like crime).
The reported health outcomes were stress, mental health, self-reported physical activity, heart rate, homicide rates, and blood lead levels. The reported health risks were crime, gun violence, insect vectors, parasites, heavy metal contamination and injuries.
Among the 11 experimental studies, 73% showed that “greening” of vacant lots improved health; 18% showed some neutral effects; and one study showed a decline in health.
Following the results, the researchers included a section on the limitations they found, to inform readers of potential areas of study.
The main limitations of the evidence presented in the articles analyzed were the narrow health outcomes investigated, small sample size, the short follow-up times, and the limited geographic scope of the studies.
Overall, however, the article provided an efficient but encompassing review of the current knowledge, as well as the gaps, about how vacant lots, and the greening of them, impact human health.
Several points are worth noting: The extensive introduction describes “pathways” – both direct and indirect – by which greenspace exposure could improve health provides valuable information for in diverse stakeholders interested in the health benefits of nature. Further, the need for longitudinal research, mentioned in the “future directions” section, is a call to action for all researchers in the field.
The Journal of Landscape and Urban Planning is one of an increasing number of journals that includes a section on policy implications of article. Including policy implications in more papers would be incredibly useful to those of us working at the intersection of research and policy outcomes.
- Olivia Poole
Source Article: Sivak, C. J., A. L. Pearson and P. Hurlburt (2021). "Effects of vacant lots on human health: A systematic review of the evidence." Landscape and Urban Planning 208: 104020. http://www.sciencedirect.com/science/article/pii/S0169204620315048
Author: Arseniy Minasov
About the Author: Arseniy Minasov is the Research Coordinator at Northwestern’s Department of Anthropology (Dr. Horton Research Group): Health Benefits of Nature. He graduated from Northwestern in 2018 with a B.A. in Biological Anthropology. He studies technology, gaming, and the intersection of nature-based interventions with technology and medicine, while also enjoying competitive gaming and triathlons.
Don’t Count VR Out of Providing the Benefits of Nature.
Virtual Reality (VR), one of the newest and most powerful technological advancements, may help connect the realms of technology and psychology. VR, used in fields of both medicine and entertainment, is a simulated environment that displaces the user through visual and auditory stimuli into another environment.
With the dual aspects of increased realism and escapism, VR may offer a replacement for visual and auditory stimulation when it comes to simulating real-world psychological benefits, such as exposure to nature and open space/green space. A VR intervention would, expectedly, be weaker than a real exposure to nature, but those for whom a real-life encounter is impossible may benefit from the virtual experience.
In a 2020 study, researchers at the University of Illinois at Urbana-Champaign sought to understand where along the spectrum of “no physical exposure to nature” to “extensive exposure to nature” VR lies. Participants indicated their “nature preferences” using beauty-and-disgust surveys. Then, in the trial, participants were randomly assigned to sit in one of three places: (A) facing a white wall, (B) outdoors in nature, or (C) indoors with a VR representation of the same nature space as group B.
Researchers measured the mood, restorativeness, and skin conductivity levels (SCL) of each participant. Overall, the study found that VR can simulate nature to some extent – with a noticeable difference between no-nature and VR when it came to mood – but VR does not come close to the real-nature intervention.
The study appears to show that VR cannot simulate nature to the extent that would be beneficial on a widespread, unconditional basis. There are, however, several limitations in the study that merit additional attention.
First, the VR technology used in the study was from 2015 and found on a Samsung smartphone – not a stand-alone or PC-compatible native VR headset. The differences in quality between those are stark, and despite dramatic advances in a phone’s VR potential in recent years, it is not nearly as powerful as some higher-end VR machines now available.
Second, the study itself mentions several of its own limitations, such as the fact that its college-student cohort was not ideal for observing changes in psychological variables. (These limitations ring true to our own studies at Northwestern University with actual nature exposure as well.) Nevertheless, with VR still in its relative technological infancy, we should not discredit or discount the idea of having these technological marvels in our own homes and potentially in hospitals to give people who need nature access the possibility of receiving it.
- Arseniy Minasov
Source Article: Browning, M., K. J. Mimnaugh, C. J. van Riper, H. K. Laurent and S. M. LaValle (2019). "Can Simulated Nature Support Mental Health? Comparing Short, Single-Doses of 360-Degree Nature Videos in Virtual Reality With the Outdoors." Frontiers in Psychology 10: 2667. https://www.ncbi.nlm.nih.gov/pubmed/32010003
An Abundance of Nature and Free Time: The COVID-19 Pandemic’s Effects on Human-Nature Interactions & Potential Policy Applications
Author: Peyton Meyer
About the Author: Growing up just outside of Madison, Wisconsin, Peyton Meyer (he/him) is an undergraduate student at Yale University, with interests in psychology, mental health advocacy, and environmentalism. As an avid cross country skier, and having served as garden chair in his hometown's community garden, Peyton has seen firsthand the unique effects that nature can have on the mind, a driving factor behind his participation in nature-based intervention research over the past year.
Amid stay-at-home orders and social distancing, human-nature interactions saw significant changes during the COVID-19 pandemic. In April 2021, Soga et al. published “Impacts of the COVID‐19 pandemic on human–nature interactions: Pathways, evidence and implications” in the journal People and Nature (Soga et al., 2021). The authors propose a conceptual framework describing the pathways by which COVID-19 may affect human-nature interactions and resulting feedback loops (Figure 1). The authors emphasize that effective policies should minimize human-nature interactions with negative consequences, and maximize those with positive consequences, to benefit individuals’ health, safety, and motivation to get outdoors.
Though its conclusion feels obvious, the framework merits further investigation. It demonstrates how one consequence can have lasting impacts on future human-nature interactions through the three pathways and feedback loops, and how these may be modified by COVID-19 (Figure 1). Such reasoning could provide strong support for policies related to nature conservation, establishing natural spaces, and accessibility of natural spaces.
A positive feedback loop would lead to further increases in human-nature interactions. For example, if people have more free time to spend with nature (Pathway 1), which improves their mental health (Pathway 2), this may increase motivation for future visits to nature (Pathway 3). A negative feedback loop would be where increases in human-nature interactions lead to decreases, or vice versa. For example, again, if people have more free time to spend with nature (Pathway 1), they may have more chances of injuring themselves while out (Pathway 2). The natural areas’ quality could also decrease from overuse without proper maintenance, which could lead to people being less interested in spending their time there (Pathway 3).
Looking deeper, the study can be broken into three key parts: an initial investigation of the pandemic’s impacts on human-nature interactions, creating the conceptual framework, and an analysis of potential feedback loops. Human-nature interactions were investigated using data from around the world recorded before and during the pandemic. The data analyzed ranges from greenspace/forest visits to wildlife-vehicle collisions per day (Figure 2)
Though often increasing in quantity, the data suggest that human-nature interaction frequency during the pandemic likely depends on where a person lives and the local norms/policies. Greenspace/forest visits are seen to increase in graphs a-d, while decreasing in the UK (e) (Figure 2). Further, wildlife observations decreased in South Africa and wildlife-vehicle collisions decreased in California. Overall, it is the conceptual framework that could explain the variety of these results. Thus, the conceptual framework shows real promise for applications to reasoning and supporting related policies.
- Peyton Meyer
Source Article: Source Article: Soga, M., M. J. Evans, D. T. C. Cox and K. J. Gaston (2021). "Impacts of the COVID‐19 pandemic on human–nature interactions: Pathways, evidence and implications." People and Nature. https://besjournals.onlinelibrary.wiley.com/doi/pdfdirect/10.1002/pan3.10201