Urban agglomerations expose citizens to ever-increasing risks from heat, air pollution,
noise stress, and reduced nature connectedness. Concurrently, accumulating evidence
suggests various health benefits by exposure to urban natural spaces (World Health
Organization, 2016a; Bratman et al., 2019). Existing research suggests an array of
benefits of contact with nature which are linked to physical activity (e.g., green
exercise), active travel, and residential proximity to greenspace. Psychological benefits
appear to be related to mood, well-being, attention and pro-environmental behavior;
physiological benefits have been described in terms of increased physical activity,
improved cardiovascular parameters, reduced stress hormones, and enhanced immune resources
(Bowler et al., 2010; Li, 2010; Park et al., 2010; Calogiuri and Chroni, 2014; Hartig
et al., 2014; van den Bosch and Sang, 2017).
Nature offers a low-cost non-invasive solution for mental health and well-being with
the potential to reduce inequities. This has never been so relevant. COVID-19 related
restrictions on mobility and associated reduced (or lack of) access to many recreational
venues, has meant that engaging with nature, by visiting nearby natural environments
(Samuelsson et al., 2020) or through home gardening (Walljasper and Polansek, 2020)
has been an important means of staying active and managing stress—in some case also
to mitigate food insecurity. Technology, especially emerging technologies such as
virtual reality (VR), can also facilitate human-(virtual) nature interactions when
contact with real nature is not possible (Litleskare et al., 2020).
Environmental psychology has helped us to understand human-nature interactions from
a transactional perspective (Gifford, 2013). Ecosystems services have been applied
to explain the benefits and risks of such interactions (Bratman et al., 2019). More
recently, nature-based solutions (NBS) have come to the fore supported by the EU Biodiversity
strategy 2030, UN Global Compact and the IUCN global standard for NBS. There is a
growing scientific imperative in achieving consensus on the optimum measures, methodological
approaches, theoretical frameworks, and concepts to enhance our understanding of human-nature
interactions (Frantzeskaki, 2019). The race for upscaling and proliferation of NBS
has commenced and yet the speed of advancement of conceptual understanding and methodological
rigor lags behind. Despite more than three decades of research since the advent of
the biophilia hypothesis, researchers' conclusions have been limited by methodological
challenges. Few studies have employed measures that are directly comparable with national
or international surveys (e.g., WHO-5). Theoretical assumptions from environmental
psychology have not been readily supported by models based on biological plausibility
or neural implementation. A range of methodological approaches in the assessment of
predisposing factors including nature connectedness and prior experience has limited
the capacity of systematic reviews to conduct reliable comparisons (Lahart et al.,
2019). Standardization of measures and conceptual clarity among researchers would
facilitate more robust research, cross-cultural comparisons and provide clearer evidence
for the future decisions on investment in nature-based solutions with the capacity
to address many societal challenges.
In launching this Research Topic, our objective was to capture contemporary perspectives
on the conceptualization and measurement of human-nature interactions, and advance
future research perspectives. The ubiquitous nature of the challenge is exemplified
by a diverse and expansive list of countries of our contributors, which ranges among
15 different countries including Australia, Brazil, Denmark, Finland, Germany, Ireland,
Norway, Peru, Portugal, Singapore, South Africa, Spain, Switzerland, the UK, and the
USA. Twenty articles were included in the collection. These included an array of approaches,
with nine original research articles, two brief research report articles, four perspective
articles, two reviews, and three systematic reviews. Many provide novel viewpoints
in our understanding of human-nature interactions, in relation to both, the effects
of being in contact with nature and potential underlying mechanisms explaining the
relationship. More specifically, the articles included in this collection have investigated
the extent to which exposure to nature can affect indices of physical and mental health
(Berry et al.; Gritzka et al.; Mygind et al.), psychophysiological parameters (Becker
et al.; Browning, Mimnaugh et al.; Hunter et al.; Litleskare and Calogiuri; Reeves
et al.), cognitive restoration (Olszewska-Guizzo et al.; Stevenson et al.), and environmental
attitudes and behaviors (Rosa and Collado). Two articles evaluated “best-dose” of
nature exposure, i.e., the most effective amount of time required to obtain health
benefits (Hunter et al.; Meredith et al.).
Several of the included articles have investigated or discussed possible explanations
for the health and restorative benefits of interacting with nature. These included
studies on brain activity associated with perception of natural environments (Mahamane
et al.; Olszewska-Guizzo et al.; Reeves et al.), the impact of scene oscillations
on psychological responses to exposure to virtual nature (Litleskare and Calogiuri),
and how eye movements contribute to explain restorative processes (Stevenson et al.).
Two studies have investigated the impact of being exposed to natural environments
on health-related behaviors that may, in turn, contribute explaining the health effects
of interacting with nature; these included physical activity (Becker et al.) and healthy
decision-making (Berry et al.). One article proposed a theoretical framework that
can be adopted to conceptualize the complex human-nature interaction (Brymer et al.).
Two articles examined the relationship between the concepts of nature connectedness
and social relational values (Kleespies and Dierkes) or between the concepts of nature
connectedness and emotions (Petersen et al.), whereas Render et al. explored the association
between individuals' personality and their choice of work environment. Other topics
included related to challenges encountered by interdisciplinary research groups (Berry
et al.), the conditions of captive amphibians (Measey et al.), and the concept of
place identity (Peng et al.) and vulnerability (Tallman et al.).
This Research Topic highlighted the growing interest in studying nature effects on
cognition through use of cutting-edge technologies and instruments, such as virtual
reality (VR) and measurements of brain activity. This is encouraging, as the hope
is that using more immersive, yet experimentally controlled, exposure to natural environments
increasing the precision that will allow comparison of different environment exposures
(e.g., different types of nature, built environments). Moreover, modern cognitive
neuroscience approaches such as electroencephalography (EEG) and functional magnetic
resonance imaging (fMRI) may be more useful in indicating the mechanism underlying
these nature benefits, by indicating how different brain regions are engaged between
the different experimental conditions (e.g., see Madan et al., 2019, for further background).
In the present Research Topic, several studies were based on this approach, using
VR or 3D imaging to expose participants to different environments (Browning, Mimnaugh
et al.; Litleskare and Calogiuri; Olszewska-Guizzo et al.), and/or performed objective
measurements such as EEG assessments of brain activity (Mahamane et al.; Olszewska-Guizzo
et al.; Reeves et al.), biomarkers of stress (Becker et al.; Hunter et al.; Reeves
et al.), and assessments by mobile eye-tracker (Stevenson et al.). Innovative instruments
and methodologies were also represented, with one study involving a novel approach
to implement “self-managed” nature experiences interventions in the context of daily
life (Hunter et al.) and another examining the effectiveness of using a novel low-cost
wearable technology to conduct in-loco assessments of brain activity and biomarkers
of stress (Reeves et al.).
The rationale for this Research Topic was to advance the methodological rigor in the
field and the research appears to have supported the need for such an approach. For
example, quality of the evidence was often deemed low in both systematic reviews (Gritzka
et al.; Mygind et al.) and this had recently been reported in the broader literature
(Lahart et al., 2019). This limiting factor inhibited both analyses and effect sizes
were thus not calculated in either study. With this in mind and the aforementioned
discourse, we present our recommendations for future research.
Recommendations
On the base of wider literature and emerging knowledge in this field, as well as the
new knowledge generated through the articles included in this Research Topic, we highlight
the following recommendations for future research:
Nature experiences during COVID19 pandemic—The COVID19 global pandemic brought to
the fore the need to increase both the access and availability of nature in urban
areas for multifunctional inter-generational social, physical, and mental health (Nieuwenhuijsen,
2020). One learning point for the field is that the transactional viewpoint of ecosystem
services (for health) does not adequately address the complex interactions between
humans and nature. Investment in nature-based solutions by the EU, for example, highlights
that transdisciplinary approaches more readily capture for the potential reciprocal
benefits. Within the Research Topic a wealth of theoretical approaches had been applied
(e.g., ecological systems) which pivoted beyond the traditional dichotomous approach
of Stress Reduction Theory and Attention Restoration Theory. As the published papers
in this Research Topic have demonstrated, theory-driven research using diverse explanatory
frameworks are recommended to enable the research of today to resonate far into the
future.
Nature Exposure and Experience—A parsimonious approach focused on dose-response effects
may overlook the role of the participants' attention or mindset during nature exposure.
To this end, Bratman et al. (2019) refer to the nature experience as comprising both
“dose” and “interaction”; i.e., the specific ways in which people interact with nature
may account for differential impacts of nature exposure on health-related outcomes.
Nature connectedness is a key variable that requires further insight-do we need an
urban nature connectedness construct? Furthermore, there is a need to account for
other factors including natural environment quality (a potential factor of inequality,
World Health Organization, 2016b), the attention of the participant and their perception
of the setting.
Immersive technology to enhance methodological rigor—Use of immersive technology such
as virtual reality (VR) and, especially, immersive-virtual environments (IVE) offers
great opportunities for conduction experiments in highly controlled conditions. While
we encourage researchers to make use of this technology in experimental design to
enhance methodological rigor, we also warn about challenges associated with this technology.
While VR and IVE technology can provide more vivid experiences of nature as compared
to non-immersive virtual exposure (e.g., videos or pictures), recent analyses show
that exposure to virtual nature provides psychological responses to a lesser extent
than real nature (Browning et al., 2020). This needs to be taken into account when
interpreting findings of experiments using environmental exposure via VR or IVE. At
the same time, we encourage more studies that aim to understand how to improve the
quality of virtual nature experiences.
Technological nature to promote and augment human-nature interactions—Recently attention
has been drawn to the role technological nature (especially in form VR, augmented
reality, and mobile applications) in promoting and augmenting human-nature interactions,
particularly among groups of individuals with limited access to real nature (Litleskare
et al., 2020). Studies in this field are extremely scarce, thus we encourage researchers
to explore the effectiveness of different approaches as well as their underlying mechanisms.
Multidimensional health—An array of methods have been employed in an attempt to comprehensively
account for the possible positive and negative impacts of human nature interactions.
Subjective scales, objective markers (e.g., EEG), and biomarkers (e.g., cortisol)
can provide converging evidence for the impact and will potentially expand the range
of factors to be considered in the future. For instance, the construct of psychological
resilience, has rarely been subject to study by researchers in this field despite
the obvious overlap with the concept of resilience in natural systems. A broad view
of health could also enable greater generalizability across settings from the workplace
to the classroom, to the urban and rural communities supported by a broad consensus
or standardization in the measures of the common constructs and outcomes.
Interdisciplinary and Transdisciplinary—The evidence presented in this Research Topic
and our recommendations are not specific to one field or discipline but have implications
across the broader field beyond environmental psychology. Environmental psychology,
after four decades could benefit from a reset on the approaches required to address
the ever-pressing wicked problems of climate change, biodiversity deficit, environmental
degradation, rapid urbanization, and global pandemics.
Our actions, decisions and omissions are so closely intertwined with ecological effects
that they can hardly be considered separately (Stokols, 2018). Nature provides a potential
low stigma and low risk intervention, and the benefits for human and environmental
health are potentially reciprocal. These complex inter-relationships requires theory
driven questions, sophisticated methods and complex analyses. By advancing the concepts
and methods a window of opportunity opens for human nature interactions to be more
clearly elucidated.
Author Contributions
All authors listed have made a substantial, direct and intellectual contribution to
the work, and approved it for publication.
Conflict of Interest
The authors declare that the research was conducted in the absence of any commercial
or financial relationships that could be construed as a potential conflict of interest.