Physiological Effects of Touching Coated Wood

Antistress Effects of Terpinen-4-ol and Compounds of Mimicked Yuzu Synthetic Fragrance in Humans and Mice

This study investigated the antistress effects of yuzu synthetic fragrances by employing three experiments on humans and mice using two yuzu synthetic fragrances and five single compounds. We prepared two synthetic fragrances based on the component analysis of two natural yuzu essential oils extracted by cold-pressed and steam-distilled extraction methods. Chromogranin A (CgA) and heart rate (HR) were used as stress indices in human experiments. Immobility time during the forced swim test was used as a stress index in mice experiments. We analyzed brain mechanisms by measuring the expression of neurotrophic factors, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and neurotrophin-3 (NT-3) in the mice experiments. Synthetic yuzu fragrance mimicked steam-distilled oil (SD) significantly reduced participants' heart rate in experiment 1. In the forced swim test conducted in experiment 2, SD significantly reduced immobility time, and increased the expression of neurotrophic factors BDNF, NGF, and NT-3 in the hippocampus of mice. In experiment 3, focusing on single compounds, terpinen-4-ol significantly reduced immobility time in the forced swim test. These findings indicate that inhalation of SD and terpinen-4-ol has antistress effects. Terpinen-4-ol is a strong candidate for further investigation as a potential stress-reducing agent.

State of science: refitting the human to nature

Environmental institutions are realising that the human-nature relationship is a tangible target for a sustainable future. Societal change of that relationship is a challenge involving modifications to both systems and human behaviours. We argue that as Human Factors and Ergonomics (HFE) focusses on relationships, interfaces and systems it is well placed to contribute. After introducing the state of HFE and nature connectedness science an analysis of areas of HFE and human-nature connectedness themes is used to consider current work and future opportunities. We conclude that despite decades-old calls to action, HFE is embedded in a dated paradigm and has had little positive contribution to the human-nature relationship. However, HFE is well placed to create sustainable communities, designed to create a new relationship with nature. To do this, HFE needs to recognise that it should move on from solely fitting the task to the human, to refitting the human to nature.Practitioner Summary: A more sustainable human-nature relationship can be achieved through applying HFE approaches. HFE expertise in human characteristics, systems, people and technology can be applied at differing scales with various social-economic and technical factors to address key themes in our failing relationship with nature.Abbreviations: HFE: Human Factors and Ergonomics; IPBES: Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services; STAMP: System-Theoretic Accident Model and Processes; CWA: Cognitive Work Analysis; NET-HARMS: NETworked Hazard Analysis and Risk Management System; NbS: Nature-based System.

The effect of exposure to natural sounds on stress reduction: a systematic review and meta-analysis

The main aim of this review is to compare whether natural sounds or a quiet environment is more beneficial for alleviating stress. The results showed that there is a statistically significant difference between exposure to natural sounds and a quiet environment in terms of their effect on heart rate (p = 0.006), blood pressure (p = 0.001), and respiratory rate (p = 0.032). However, no significant difference was found between exposure to natural sounds and a quiet environment in terms of their effect on MAP (p = 0.407), perceived stress, and SPO2 (p = 0.251). Although the evidence was slightly inconsistent, overall, natural sounds were found more beneficial for stress reduction than quiet environments.

Physiological Effects of Visual Stimulation by a Japanese Low Wooden Table: A Crossover Field Experiment

The purpose of this study was to evaluate the physiological effects of visual stimulation by a unique Japanese low wooden table on the prefrontal cortex and autonomic nervous activities. A within-participants experiment with 26 male university students was conducted in a Japanese-style room. The visual stimuli were a low wooden table (WT) made of Japanese cypress and a low cloth-covered table (control) for an exposure time of 90 s. Near-infrared spectroscopy was used to measure the prefrontal cortex activity in the left and right prefrontal cortices as an indicator of oxyhemoglobin (oxy-Hb) concentration. Autonomic nervous activity was measured as an indicator of sympathetic (low-frequency/high-frequency component ratio, LF/HF), and parasympathetic (high-frequency components, HF) nervous activities were assessed by heart rate variability. Furthermore, the modified semantic differential method and the Profile of Mood States 2nd edition were used to measure psychological responses. Physiologically, the oxy-Hb concentration in the left prefrontal cortex and ln (LF/HF) were significantly lower during visual exposure to the WT than to the control. Psychologically, more comfortable, relaxed, and natural impressions, as well as improved mood states, were reported during visual stimulation to the WT than to the control. This study demonstrated that viewing a WT led to physiological relaxation and had a positive psychological effect on the participants.

Physiological adjustment effect of visual stimulation by fresh rose flowers on sympathetic nervous activity

Introduction

As modern societies are often stressful due to urbanization and artificialization, the physiological relaxing effects of natural environments or nature-derived stimuli on humans have attracted attention and scientific data are being accumulated. It is known that there is inter-individual variation in these effects. The study aim was to apply the law of initial values to investigate the physiological adjustment effect of viewing fresh roses on sympathetic nervous activity.

Methods

In this crossover study, a total of 214 high school students, office workers, healthcare workers, and elderly people were analyzed. The participants viewed fresh roses in a vase for 4 min. In the control condition, participants did not view any fresh roses during the period. To offset any order effect, participants received visual stimuli in the order of fresh roses then the control (no fresh roses) or the control and then fresh roses. ln (LF/HF) of heart rate variability (HRV) obtained from a-a interval measurements using an acceleration plethysmograph and used as an index of sympathetic nervous activity. The initial value was ln (LF/HF) of HRV during the control viewing (no fresh roses), and the change value was ln(LF/HF) of HRV during visual stimulation by fresh roses minus the control viewing.

Results and Discussion

The correlation between the two was assessed by determining Pearson's correlation coefficient r, which was significantly negative. A physiological adjustment effect was observed such that participants with high initial sympathetic nervous activity showed a decrease in activity after visual stimulation with fresh roses, whereas participants with low initial activity showed an increase.

Thermal effusivity of different tabletop materials in relation to users' perception

Tactile interaction between humans and elements in the built environment, such as furniture, is often underappreciated. The aim of this study was to objectively evaluate thermal properties of ten tabletop materials as well as user perceptions of those materials after use. Sixteen participants tested ten materials in a randomised order. Infrared thermography was used to determine tabletop temperature distribution and change. Materials with lower thermal effusivity (wood-based materials) in general reached higher surface temperature differences after 15 min of contact and were rated as more pleasant to touch, more suitable for writing, and more liked for everyday use. Participants' sex and forearm mass had no effect on the temperature after contact. Participants gave the highest ratings to the appearance of oak-based materials. Surface treatment affected subjective evaluation of the materials. The tabletop made of lacquered solid wood had the most favourable thermal and user-rated characteristics.

Healthy Dwelling: Design of Biophilic Interior Environments Fostering Self-Care Practices for People Living with Migraines, Chronic Pain, and Depression

The benefits of biophilic interior design have been recognized by healthcare facilities, but residential environments receive relatively less attention with respect to improving the health of people living with chronic diseases. Recent “stay-at-home” restrictions due to the COVID-19 pandemic further emphasized the importance of creating interior spaces that directly and indirectly support physical and mental health. In this viewpoint article, we discuss opportunities for combining biophilic interventions with interior design, fostering disease-specific self-care. We provide examples of designing residential spaces integrating biophilic interventions, light therapy, relaxation opportunities, mindfulness meditation, listening to music, physical activities, aromatherapy, and quality sleep. These modalities can provide the clinical benefits of reducing migraine headaches and chronic pain, as well as improving depressive symptoms. The disease-specific interior environment can be incorporated into residential homes, workplaces, assisted-living residences, hospitals and hospital at home programs. This work aims to promote a cross-disciplinary dialogue towards combining biophilic design and advances in lifestyle medicine to create therapeutic interior environments and to improve healthcare outcomes.

Glossiness Evaluation of Coated Wood Surfaces as Function of Varnish Type and Exposure to Different Conditions

The objective of this study was to evaluate the glossiness of black alder wood (Alnus glutinosa L.) samples coated with two varnish types as a function of exposure to dry heat and artificial aging. The chemical resistance of the coated samples to cold liquids was also evaluated. Based on the findings in this work, it appears that the varnish types and their structural differences influenced the overall glossiness of the coated samples. The UV varnish exhibited higher gloss values than those coated with the water-borne product within the range of silky gloss and silky matte grades. The heat exposure influenced the surface glossiness of the UV-coated samples more than the samples coated with water-borne varnish. The overall gloss values of the samples decreased with the exposure time to artificial aging, resulting in no layer cracks. The cold household liquids left less visible traces on the surfaces and alcohol was found to be the strongest agent. This study could have practical applications in the furniture industry to produce value-added furniture units according to their specific conditions of indoor use.

Effects of Integrated Indirect Forest Experience on Emotion, Fatigue, Stress and Immune Function in Hemodialysis Patients

BACKGROUND

Most hemodialysis patients may experience physiological and psychological stress. Exposure to nature has been reported to reduce psychological and physiological stress levels and improve immune function. This study aimed to investigate psychological and physiological effects of integrated indirect forest experience on chronic renal failure patients undergoing hemodialysis.

METHODS

As a quasi-experiment, this study employed a nonequivalent control group, repeated measurements, and a non-synchronized design. In total, 54 participants were included: 26 and 28 patients in the experimental and control groups, respectively. During hemodialysis, five types of forest therapy stimuli (visual, auditory, olfactory, tactile, and motor) were applied 3 times per week for 4 weeks during 15 min sessions.

RESULTS

Positive, but not negative, emotion measures differed between the groups after the intervention. Fatigue and physiological stress levels were significantly reduced in the experimental group, whereas no significant difference was found between the groups with respect to measures of psychological stress. Activation of both the parasympathetic and sympathetic nervous systems was similar in both groups, as was the number of natural killer cells.

CONCLUSION

Integrated indirect forest experience may help increase positive emotions and reduce fatigue and stress levels during hemodialysis in patients with chronic renal failure.

The finishing touches: the role of friction and roughness in haptic perception of surface coatings

Humans are extraordinarily skilled in the tactile evaluation of, and differentiation between, surfaces. The chemical and mechanical properties of these surfaces are translated into tactile signals during haptic exploration by mechanoreceptors in our skin, which are specialized to respond to different types of temporal and mechanical stimulation. Describing the effects of measurable physical characteristics on the human response to tactile exploration of surfaces is of great interest to manufacturers of household materials so that the haptic experience can be considered during design, product development and quality control. In this study, methods from psychophysics and materials science are combined to advance current understanding of which physical properties affect tactile perception of a range of furniture surfaces, i.e., foils and coatings, thus creating a tactile map of the furniture product landscape. Participants’ responses in a similarity scaling task were analyzed using INDSCAL from which three haptic dimensions were identified. Results show that specific roughness parameters, tactile friction and vibrational information, as characterized by a stylus profilometer, a Forceboard, and a biomimetic synthetic finger, are important for tactile differentiation and preferences of these surface treatments. The obtained dimensions are described as distinct combinations of the surface properties characterized, rather than as ‘roughness’ or ‘friction’ independently. Preferences by touch were related to the roughness, friction and thermal properties of the surfaces. The results both complement and advance current understanding of how roughness and friction relate to tactile perception of surfaces.

Physiological Benefits of Viewing Nature: A Systematic Review of Indoor Experiments

Contact with nature has been proposed as a solution to achieve physiological relaxation and stress recovery, and a number of scientific verification outcomes have been shown. Compared with studies of the other senses, studies investigating the visual effects of nature have been at the forefront of this research field. A variety of physiological indicators adopted for use in indoor experiments have shown the benefits of viewing nature. In this systematic review, we examined current peer-reviewed articles regarding the physiological effects of visual stimulation from elements or representations of nature in an indoor setting. The articles were analyzed for their stimulation method, physiological measures applied, groups of participants, and outcomes. Thirty-seven articles presenting evidence of the physiological effects of viewing nature were selected. The majority of the studies that used display stimuli, such as photos, 3D images, virtual reality, and videos of natural landscapes, confirmed that viewing natural scenery led to more relaxed body responses than viewing the control. Studies that used real nature stimuli reported that visual contact with flowers, green plants, and wooden materials had positive effects on cerebral and autonomic nervous activities compared with the control. Accumulation of scientific evidence of the physiological relaxation associated with viewing elements of nature would be useful for preventive medicine, specifically nature therapy.

Physiological and Psychological Effects of Forest and Urban Sounds Using High-Resolution Sound Sources

Exposure to natural sounds is known to induce feelings of relaxation; however, only few studies have provided scientific evidence on its physiological effects. This study examined prefrontal cortex and autonomic nervous activities in response to forest sound. A total of 29 female university students (mean age 22.3 ± 2.1 years) were exposed to high-resolution sounds of a forest or city for 60 s, using headphones. Oxyhemoglobin (oxy-Hb) concentrations in the prefrontal cortex were determined by near-infrared spectroscopy. Heart rate, the high-frequency component of heart rate variability (which reflects parasympathetic nervous activity), and the ratio of low-frequency to high-frequency (LF/HF) components (which reflects sympathetic nervous activity) were measured. Subjective evaluation was performed using the modified semantic differential method and profiles of mood states. Exposure to the forest sound resulted in the following significant differences compared with exposure to city sound: decreased oxy-Hb concentrations in the right prefrontal cortex; decreased ln(LF/HF); decreased heart rate; improved feelings described as "comfortable,'' "relaxed," and "natural"; and improved mood states. The findings of this study demonstrated that forest-derived auditory stimulation induced physiological and psychological relaxation effects.

Physiological Effects of Touching the Wood of Hinoki Cypress (Chamaecyparis obtusa) with the Soles of the Feet

We clarified the physiological effects of tactile stimulation of the soles of the feet with the wood of the Hinoki cypress (Chamaecyparis obtusa) based on measurements of prefrontal cortex and autonomic nervous activities. Nineteen female university-attending students (age: 21.2 ± 0.3 years) were included. Oxy-hemoglobin (oxy-Hb) concentrations in the prefrontal cortex were determined by using near-infrared time-resolved spectroscopy. The high frequency (HF) indicating parasympathetic nervous activity and the ratio of low frequency (LF)/HF indicating sympathetic nervous activity were measured using heart rate variability. To evaluate the psychological effects caused by contact with the materials, the modified semantic differential method was used. The soles of the participants' feet were touched to a 600 × 600-mm plate made of Hinoki, which was finished in non-coating and brushing for 90 s. A marble plate served as the control. Next, subjective evaluation tests were administered to the participants. Compared with touching marble, touching Hinoki significantly (1) decreased the oxy-Hb concentrations in the left and right prefrontal cortices, which indicates decreased prefrontal cortex activity, (2) increased ln(HF), which indicates increased parasympathetic nervous activity, (3) decreased ln(LF/HF) ratio, which indicates decreased sympathetic nervous activity. Additionally, (4) according to subjective evaluations, the participants perceived themselves as being more "comfortable," "relaxed," "natural," "warm," "uneven," "dry," and "soft" after touching Hinoki. Thus, our cumulative findings indicate that touching Hinoki with the soles of the feet induces physiological relaxation.