Nature, smells, and human wellbeing

A framework for understanding the human experience of nature through cognitive mapping

Human behavior is a key driver of the biodiversity crisis, and addressing it requires changing individual choices and actions. Yet, the same processes that imperil biodiversity (e.g., urbanization) also alienate people from the experience of nature, eroding care for the natural world. Although averting this extinction of experience is increasingly recognized as a major contemporary conservation challenge, understanding of what constitutes nature experience remains elusive and few empirical studies have explored it directly. Most researchers have used nature interactions as a stand-in for experience, even though experience extends beyond interactions. We aimed to determine what constitutes the experience of nature and to propose a holistic, empirically derived framework that incorporates the multiple dimensions and components of the experience of nature. Using a mixed-method approach across 3 countries (the United States, Switzerland, and Israel), we conducted a multistage, conceptual content, cognitive mapping (3CM) exercise with 106 participants. This methodology included developing a prompt to capture participants' perceptions of nature experiences and subsequently refining and organizing their input into distinct components and underlying dimensions through an iterative engagement process. Beyond multisensory interactions with nature, experience of nature consisted of 2 dimensions: the circumstances in which interactions occur and the internal responses that encompass various cognitive, affective, and restorative benefits associated with nature interactions. These 3 dimensions had 33 components that occurred consistently across participants in the 3 countries. Frequently mentioned components included seeing animals, landscapes, or scenery; lack of human influence; weather conditions; relaxing, recharging; feeling good; and awe for nature. Fear and nature experienced at home were the least mentioned components. Together, our results showed that nature experience is a combination of nature interactions, circumstances, and internal responses. The emphasized components underscore the significance of offering access to extensive, less human-influenced natural spaces. This in turn can foster a profound nature experience, cultivating feelings of connectedness and care for nature.

Wilding cities for biodiversity and people: a transdisciplinary framework

Accelerating urbanisation and associated lifestyle changes result in loss of biodiversity and diminished wellbeing of people through fewer direct interactions and experiences with nature. In this review, we propose the notion of urban wilding (the promotion of autonomous ecological processes that are independent of historical land-use conditions, with minimal direct human maintenance and planting interventions) and investigate its propensity to improve biodiversity and people-nature connections in cities. Through a large interdisciplinary synthesis, we explore the ecological mechanisms through which urban wilding can promote biodiversity in cities, investigate the attitudes and relations of city dwellers towards urban wild spaces, and discuss the integration of urban wilding into the fabric of cities and its governance. We show that favouring assembly spontaneity by reducing planting interventions, and functional spontaneity by limiting maintenance practices, can promote plant diversity and provide ecological resources for numerous organisms at habitat and city scales. These processes could reverse biotic homogenisation, but further studies are needed to understand the effects of wilding on invasive species and their consequences. From a socio-ecological perspective, the attitudes of city dwellers towards spontaneous vegetation are modulated by successional stages, with grassland and woodland stages preferred, but dense shrubby vegetation stages disliked. Wild spaces can diversify physical interactions with nature, and enrich multi-sensory, affective and cognitive experiences of nature in cities. However, some aspects of wild spaces can cause anxiety, feeling unsafe, and the perception of abandonment. These negative attitudes could be mitigated by subtle design and maintenance interventions. While nature has long been thought of as ornamental and instrumental in cities, urban wilding could help to develop relational and intrinsic values of nature in the fabric of cities. Wildness and its singular aesthetics should be combined with cultural norms, resident uses and urban functions to plan and design urban spatial configurations promoting human-non-human cohabitation. For urban wilding to be socially just and adapted to the needs of residents, its implementation should be backed by inclusive governance opening up discussion forums to residents and urban workers. Scientists can support these changes by collaborating with urban actors to design and experiment with new wild spaces promoting biodiversity and wellbeing of people in cities.

Nature and human well-being: The olfactory pathway

The world is undergoing massive atmospheric and ecological change, driving unprecedented challenges to human well-being. Olfaction is a key sensory system through which these impacts occur. The sense of smell influences quality of and satisfaction with life, emotion, emotion regulation, cognitive function, social interactions, dietary choices, stress, and depressive symptoms. Exposures via the olfactory pathway can also lead to (anti-)inflammatory outcomes. Increased understanding is needed regarding the ways in which odorants generated by nature (i.e., natural olfactory environments) affect human well-being. With perspectives from a range of health, social, and natural sciences, we provide an overview of this unique sensory system, four consensus statements regarding olfaction and the environment, and a conceptual framework that integrates the olfactory pathway into an understanding of the effects of natural environments on human well-being. We then discuss how this framework can contribute to better accounting of the impacts of policy and land-use decision-making on natural olfactory environments and, in turn, on planetary health.

Evaluating the effectiveness of applying aroma seals to masks in reducing stress caused by wearing masks: A randomized controlled trial

During the COVID-19 pandemic, face masks on patients and healthy people have been recommended to prevent airborne transmission of the virus. This increased the number of people who felt stressed while wearing masks. In this study, we investigated the stress-relieving effects of attaching aroma seals to masks. A double-blind, randomized controlled trial was conducted involving 62 university students. The participants were randomly assigned to two groups and instructed to apply a seal to their masks once a day throughout the study period. The primary measure used was the Depression, Anxiety, and Stress Scale-21 (DASS-21), while the secondary measures included the assessment of breathlessness associated with mask-wearing and the World Health Organization Five Well-Being Index (WHO-5). The intervention group, referred to as the aroma-seal use group, utilized aroma seals infused with orange-lime essential oil with the expectation of experiencing the healing effects of citrus. On the other hand, the non-intervention group, known as the placebo-seal use group, utilized identical seals without any aroma. Results indicated that the aroma-seal use group exhibited significant improvements in both the total DASS-21 scores and depression scores compared to their baseline values by the second week of the intervention. Furthermore, the aroma-seal use group demonstrated a reduced occurrence of breathlessness while wearing masks compared to the placebo-seal group. Additionally, when assessing the item "I have felt calm and relaxed" from the WHO-5 questionnaire, the aroma-seal use group displayed significantly higher scores than the placebo group. Therefore, using aroma seals containing orange-lime essential oil could be beneficial in relieving mental stress and reducing breathlessness while wearing a mask, thus improving mental health.

Restorative Effects of Biophilic Workplace and Nature Exposure during Working Time: A Systematic Review

The work environment plays a crucial role in the health and performance of employees. The growing interest in workers' well-being has driven the inclusion of nature in workplaces, despite many employees spending most of their time indoors, away from nature. Studies show that biophilic design in offices can have positive effects and promote workers' well-being. However, research on the beneficial effects of nature exposure in the workplace is limited and scattered. Thus, the aim of this systematic review was to consolidate current knowledge on the restorative effects of nature exposure on workers during work activities. Different types of exposure, both outdoors and indoors, were considered, with a focus on outcomes related to well-being, motivation, job satisfaction, and work performance. Out of the initially identified 1225 articles, only 16 met the criteria for analysis. Although the analysed studies provided compelling evidence regarding the restorative effects of nature exposure in the workplace, the review also points out gaps and limitations concerning the number of specific studies in this area and the need to adequately assess the sensory dimensions involved in these effects. Conducting more comprehensive and multidimensional investigations into the impacts of nature on the work environment could contribute to guiding more effective design strategies and creating healthier and more productive workplaces for employees.

The impact of small-scale green infrastructure on the affective wellbeing associated with urban sites

The largest public space in any city is its streets. Investments which incorporate small-scale green infrastructure into streetscapes can bring more nature into the lives of urban residents worldwide, including those living in even the most economically and spatially constraint places. However, little is known about the impact of such small-scale investments on urban residents' affective perceptions of their local environments and how to design these investments to maximise their positive impacts. In the current study, we use photo simulation techniques and an adapted form of the Positive and Negative Affective Schedule to examine the impact of small-scale green infrastructure interventions on the affective perceptions of low, middle and high-income sites in Santiago Chile. Our results, based on 62,478 reports of affective perceptions from 3,472 people, indicate that green infrastructure investments can both promote positive affect and, to a lesser, but still substantial extent reduce negative affect. The magnitudes of these relationships vary across discrete affective measures and for many of these measures, both positive and negative, a minimum of 16% increase in green coverage is required to see an impact. Finally, we find people associated lower affect with low, compared to middle and high, income sites but that these affective inequalities can be addressed, at least in part, through green infrastructure interventions.

Odor Perception and Descriptions of Rose-Scented Geranium Pelargonium graveolens 'Dr. Westerlund'-Sensory and Chemical Analyses

A recent study found that the natural scent from the rose-scented geranium Pelargonium graveolens 'Dr. Westerlund' had positive effects on stress reduction. Essential oils from many pelargonium species are known to have phytochemical properties and pharmacological activities. No study has, so far, explored and identified the chemical compounds and the sensory perception of these compounds in 'Dr. Westerlund' plants. Such knowledge would be an important contribution to an increased understanding of the effects of plants' chemical odor properties on human well-being, and link this to the expressed perceived scents. This study aimed to identify the sensory profile and suggest responsible chemical compounds of Pelargonium graveolens 'Dr. Westerlund'. The sensory and chemical analysis results revealed sensory profiles of Pelargonium graveolens 'Dr. Westerlund's and provided suggestions for the chemical compounds attributed to the sensory profiles. Further studies are recommended to investigate the correlation between volatile compounds and possible stress reduction in humans.

Artificial Olfactory Biohybrid System: An Evolving Sense of Smell

The olfactory system can detect and recognize tens of thousands of volatile organic compounds (VOCs) at low concentrations in complex environments. Bioelectronic nose (B-EN), which mimics olfactory systems, is becoming an emerging sensing technology for identifying VOCs with sensitivity and specificity. B-ENs integrate electronic sensors with bioreceptors and pattern recognition technologies to enable medical diagnosis, public security, environmental monitoring, and food safety. However, there is currently no commercially available B-EN on the market. Apart from the high selectivity and sensitivity necessary for volatile organic compound analysis, commercial B-ENs must overcome issues impacting sensor operation and other problems associated with odor localization. The emergence of nanotechnology has provided a novel research concept for addressing these problems. In this work, the structure and operational mechanisms of biomimetic olfactory systems are discussed, with an emphasis on the development and immobilization of materials. Various biosensor applications and current developments are reviewed. Challenges and opportunities for fulfilling the potential of artificial olfactory biohybrid systems in fundamental and practical research are investigated in greater depth.

Sensehacking the guest's multisensory hotel experience

This narrative review discusses the literature on contemporary sensory marketing as it applies to hotel design. The role of each of the guest's senses in the different stages of the customer journey are highlighted, and the functional benefits (to the guest's multisensory experience), and likely commercial gains, of engaging more effectively with the guest's non-visual senses, both individually, and in combination, are reviewed. While the visual elements of hotel design are undoubtedly important, the hotelier neglects the non-visual senses at their peril, given the negative effect of poor design on the customers' overall multisensory experience (and ratings). A number of the crossmodal effects and multisensory interactions that have been suggested to modulate the guest's experience of hotels (and resorts) are discussed. Mention is also made of the nature effect/biophilic design and how it is increasingly being incorporated in total design to help deliver on guest/customer well-being; the latter is a theme that has grown rapidly in relevance for those working in the hospitality sector. Taken together, there are numerous opportunities for hotel managers to 'sensehack' their guests' multisensory experiences through environmental psychology The originality of this review stems from the analysis of the hierarchy of the guest's senses and an explanation of how multisensory interactions affect sensory marketing in the design of hotel experiences for guests.