宮崎 良文

With increasing attention on the health benefits of a forest environment, evidence-based research is required. This study aims to provide scientific evidence concerning the physiological and psychological effects of exposure to the forest environment on middle-aged hypertensive men. Twenty participants (58.0 +/- 10.6 years) were instructed to sit on chairs and view the landscapes of forest and urban (as control) environments for 10 min. Heart rate variability (HRV) and heart rate were used to quantify physiological responses. The modified semantic differential method was used to determine psychological responses. Consequently, the high-frequency component of HRV, a marker of parasympathetic nervous activity that is enhanced in relaxing situations, was significantly higher and heart rate was significantly lower in participants viewing the forest area than in those viewing the urban area. The questionnaire results indicated that viewing the forest environment increased "comfortable," "relaxed," and "natural" feelings than viewing the urban environment. In conclusion, viewing forest landscape produces physiological and psychological relaxation effects on middle-aged hypertensive men. (C) 2016 The Authors. Published by Elsevier GmbH.

The study's objective was to investigate the effects of foliage plants on prefrontal cortex activity and subjective assessments of psychological relaxation. In a crossover experimental design, 24 male university students in their 20s observed a container with and without foliage plants for 3 minutes while oxyhemoglobin (oxy-Hb) concentration in the prefrontal cortex was continuously measured with a portable near-infrared (NIR) spectroscopy device. Afterward, subjective evaluations of emotions were obtained via two self-report questionnaires: a modified semantic differential (SD) method and the Profile of Mood State questionnaire (POMS). Oxy-Hb concentration in the right prefrontal cortex was significantly lower in subjects who viewed the foliage plants than in those who did not, indicating a physiologically relaxed state. The subjects also reported in the SD method significantly more positive emotions (e.g., comfortable, natural, and relaxed) associated with viewing the foliage plants. In the POMS, a significant positive effect on psychological relaxation when subjects viewed the foliage plants was shown. Thus, we conclude that foliage plants have both physiological and psychological relaxation effects in males even after only short exposure.

Humans have evolved into what they are today after the passage of 6-7 million years. If we define the beginning of urbanization as the rise of the industrial revolution, less than 0.01% of our species' history has been spent in modern surroundings. Humans have spent over 99.99% of their time living in the natural environment. The gap between the natural setting, for which our physiological functions are adapted, and the highly urbanized and artificial setting that we inhabit is a contributing cause of the "stress state" in modern people. In recent years, scientific evidence supporting the physiological effects of relaxation caused by natural stimuli has accumulated. This review aimed to objectively demonstrate the physiological effects of nature therapy. We have reviewed research in Japan related to the following: (1) the physiological effects of nature therapy, including those of forests, urban green space, plants, and wooden material and (2) the analyses of individual differences that arise therein. The search was conducted in the PubMed database using various keywords. We applied our inclusion/exclusion criteria and reviewed 52 articles. Scientific data assessing physiological indicators, such as brain activity, autonomic nervous activity, endocrine activity, and immune activity, are accumulating from field and laboratory experiments. We believe that nature therapy will play an increasingly important role in preventive medicine in the future.

There is a significant positive relationship between exposure to forest environment and physical and mental health, although individual differences exist within these responses this phenomenon has raised questions in various fields. Here we show that the psychological effect of a forest environment can differ depending on a subject’s initial values. Experiments were conducted in 46 forested areas in Japan. Twelve male Japanese university students participated in each experiment (N = 552 subjects 12 subjects × 46 areas) of these, data obtained from 536 subjects (mean age, 21.6 ± 1.6 years) were used for analysis. Subjects walked around their assigned areas for 15 min and subsequently sat on chairs while viewing the landscape of their assigned areas for 15 min. The Profile of Mood State (POMS) questionnaire was used to investigate psychological responses and was applied for both conditions-before and after walking and viewing the forest areas. Changes in POMS, both after walking and viewing forest environment, were largely associated with individual differences. We analyzed the correlation between the “initial values (before walking or viewing forest area)" and “changes observed in them following the forest walking and viewing (after walking or viewing a forest area - before walking or viewing a forest area)" based on the “law of initial value (LIV)." Significant negative correlations between the “initial value” and “changes observed in them following forest walking and viewing” were shown in all subscales of “tension-anxiety," “depression-dejection," “anger-hostility," “fatigue," “confusion," and “vigor” on the POMS score. Subjects with high initial values showed a decrease in these values after walking in and viewing a forested area, whereas those with low initial values showed an increase in these values. In conclusion, the present study identified a factor of individual differences in the psychological effects of a forest environment using the subject’s initial values.

The natural environment is increasingly recognized as an effective counter to urban stress, and Forest Therapy has recently attracted attention as a relaxation and stress management activity with demonstrated clinical efficacy. The present study assessed the physiological and psychological effects of a forest therapy program on middle-aged females. Seventeen Japanese females (62.2 +/- 9.4 years; mean +/- standard deviation) participated in this experiment. Pulse rate, salivary cortisol level, and psychological indices were measured on the day before forest therapy and on the forest therapy day. Pulse rate and salivary cortisol were significantly lower than baseline following forest therapy, indicating that subjects were in a physiologically relaxed state. Subjects reported feeling significantly more comfortable, relaxed, and natural according to the semantic differential (SD) method. The Profile of Mood State (POMS) negative mood subscale score for tension-anxiety was significantly lower, while that for vigor was significantly higher following forest therapy. Our study revealed that forest therapy elicited a significant (1) decrease in pulse rate, (2) decrease in salivary cortisol levels, (3) increase in positive feelings, and (4) decrease in negative feelings. In conclusion, there are substantial physiological and psychological benefits of forest therapy on middle-aged females.

Background: In recent years, increasing attention has been paid to the physiological effects of nature-derived stimulation. The physiological relaxation effects caused by forest-derived olfactory stimuli have been demonstrated. However, there are no studies on the physiological effects of olfactory stimuli by Hinoki cypress (Chamaecyparis obtusa) leaves. We investigated the effects of olfactory stimulation by Hinoki cypress leaf oil on the left/right prefrontal cortex activity, assessed using near-infrared time-resolved spectroscopy (TRS), and on the autonomic nervous activity, assessed by measuring heart rate variability (HRV). Method: Thirteen female university students (mean age, 21.5 +/- 1.0 years) participated in the study. Physiological measurements were performed in an artificial climate maintained at 25 degrees C, 50 % relative humidity, and 230-lx illumination. Hinoki cypress leaf oil was used as an olfactory stimulation with air as the control. The odor was administered for 90 s, while the subjects sat with their eyes closed. Oxyhemoglobin (oxy-Hb) concentrations were measured in the prefrontal cortex using TRS. The high-frequency (HF) component of HRV, which is an estimate of parasympathetic nervous activity, and the low-frequency (LF)/(LF + HF) ratio, which is an estimate of sympathetic nervous activity, were measured by electrocardiography. A modified semantic differential method was used to perform subjective evaluations. Results: Olfactory stimulation by Hinoki cypress leaf oil induced a significant reduction in oxy-Hb concentration in the right prefrontal cortex and increased parasympathetic nervous activity. The subjects reported feeling more comfortable. Conclusion: These findings indicate that olfactory stimulation by Hinoki cypress leaf oil induces physiological relaxation.

In recent times, attention has been focused on the role of urban green spaces in promoting human health and well-being. However, there is a lack of evidence-based research on the physiological effects of walking in urban green areas. This study aimed to clarify the physiological and psychological effects of walking in urban parks during fall. Twenty-three males (mean age 22.3 +/- 1.2 years) were instructed to walk predetermined 15-min courses in an urban park and in a nearby city area (control). Heart rate and heart rate variability were measured to assess physiological responses, and the semantic differential method, Profile of Mood States, and State-Trait Anxiety Inventory were used to measure psychological responses. We observed that walking in an urban park resulted in a significantly lower heart rate, higher parasympathetic nerve activity, and lower sympathetic nerve activity than walking through the city area. In subjective evaluations, participants were more comfortable, natural, relaxed, and vigorous after a walk in the urban park. Furthermore, they exhibited significantly lower levels of negative emotions and anxiety. These findings provide scientific evidence for the physiological and psychological relaxation effects of walking in urban parks during fall.

Background: Salivary cortisol has been used in various fields of science as a non-invasive biomarker of stress levels. This study offers the normative reference values of cortisol measurement for healthy young males. Findings: Salivary cortisol levels were measured in 267 healthy young males (age: 21.7 +/- 1.5 years) in the early morning on two consecutive days and were analyzed by radioimmunoassay. Frequency distribution analysis was conducted with mean values of the measurements taken on the 2 days. The mean salivary cortisol level was 20.39 +/- 7.74 nmol/l (median: 19.31 nmol/l). The skewness and kurtosis of the distribution of the raw data were 0.72 and 0.68, respectively. They were both improved by a square root transformation but not by a logarithmic transformation. Conclusions: The skewness of the distribution for salivary cortisol measured in the early morning is considerably smaller than that previously reported from afternoon measurements. A "floor effect" may be an explanation for the difference in the distribution characteristics of salivary cortisol.

© 2015 by the authors; licensee MDPI, Basel, Switzerland.The physiological and psychological relaxation effects of viewing a kiwifruit (Actinidia deliciosa ‘Hayward’) orchard landscape were investigated. Seventeen Japanese adult females (46.1 ± 8.2 years) viewed a kiwifruit orchard landscape or a building site (control) for 10 min. The heart rate variability and heart rate were determined. The modified semantic differential method and the short-form Profile of Mood States were used to assess the psychological effects. Compared with viewing the building site, viewing the kiwifruit orchard landscape resulted in a significant increase in the parasympathetic activity, a marginally significant decrease in the heart rate, a significant increase in “comfortable”, “relaxed” and “natural” feelings and a significant improvement in mood states.

There is a significant positive relationship between exposure to forest environments and physical and mental health. However, there are individual differences within these responses, and this phenomenon has posed questions in various fields. Here, we show that the physiological effect of a forest environment can differ depending on a subject's initial values and that forests have a physiological adjustment effect close to an appropriate level. Subjects with high initial blood pressure and pulse rate showed a decrease in these values after walking in a forested area, whereas those with low initial values showed an increase. There was no physiological adjustment effect observed in an urban area; thus, these effects are specific to a forest environment.

Background: Developments in information technology cause a great deal of stress to modern people, and controlling this stress now becomes an important issue. The aim of this study was to examine psychological and physiological benefits of interaction with indoor plants. Methods: The study subjects were 24 young male adults at the age of 24.9 +/- 2.1 (mean +/- SD). The crossover experimental design was used to compare the differences in physiological responses to a computer task and a plant- related task. Subjects were randomly distributed into two groups. The first group (12 subjects) carried out transplanting of an indoor plant, whereas the second group (12 subjects) worked on a computer task. Then, each subject switched activities. The psychological evaluation was carried out using the semantic differential method (SDM) and physiological evaluation using heart rate variability (low- frequency (LF) and high- frequency (HF) components) and blood pressure. Results: Analysis of the SDM data showed that the feelings during the transplanting task were different from that during the computer task: the subjects felt more comfortable, soothed, and natural after the transplanting task than after the computer task. The mean value of total log[LF/(LF + HF)] (sympathetic activity) increased over time during the computer task but decreased at the end of the transplanting task, and the differences were significant. Furthermore, diastolic blood pressure was significantly lower after the transplanting task. Conclusions: Our results suggest that active interaction with indoor plants can reduce physiological and psychological stress compared with mental work. This is accomplished through suppression of sympathetic nervous system activity and diastolic blood pressure and promotion of comfortable, soothed, and natural feelings.

(韓国語)

Time spent walking and relaxing in a forest environment ("forest bathing" or "forest therapy") has well demonstrated anti-stress effects in healthy adults, but benefits for ill or at-risk populations have not been reported. The present study assessed the physiological and psychological effects of forest therapy (relaxation and stress management activity in the forest) on middle-aged males with high-normal blood pressure. Blood pressure and several physiological and psychological indices of stress were measured the day before and approximately 2 h following forest therapy. Both pre- and post-treatment measures were conducted at the same time of day to avoid circadian influences. Systolic and diastolic blood pressure (BP), urinary adrenaline, and serum cortisol were all significantly lower than baseline following forest therapy (p < 0.05). Subjects reported feeling significantly more "relaxed" and "natural" according to the Semantic Differential (SD) method. Profile of Mood State (POMS) negative mood subscale scores for "tension-anxiety," "confusion," and "anger-hostility," as well as the Total Mood Disturbance (TMD) score were significantly lower following forest therapy. These results highlight that forest is a promising treatment strategy to reduce blood pressure into the optimal range and possibly prevent progression to clinical hypertension in middle-aged males with high-normal blood pressure.

The relaxation effects of gardening have attracted attention; however, very few studies have researched its physiological effects on humans. This study aimed to clarify the physiological and psychological effects on high school students of viewing real and artificial pansies. Forty high school students (male: 19, female: 21) at Chiba Prefectural Kashiwanoha Senior High School, Japan, participated in this experiment. The subjects were presented with a visual stimulation of fresh yellow pansies (Viola x wittrockiana "Nature Clear Lemon") in a planter for 3 min. Artificial yellow pansies in a planter were used as the control. Heart rate variability was used as a physiological measurement and the modified semantic differential method was used for subjective evaluation. Compared with artificial pansies, visual stimulation with real flowers resulted in a significant decrease in the ratio of low- to high-frequency heart rate variability component, which reflects sympathetic nerve activity. In contrast, high frequency, which reflects parasympathetic nerve activity, showed no significant difference. With regard to the psychological indices, viewing real flowers resulted in "comfortable", "relaxed", and "natural" feelings. The findings indicate that visual stimulation with real pansies induced physiological and psychological relaxation effects in high school students.

There has been increasing attention on the therapeutic effects of the forest environment. However, evidence-based research that clarifies the physiological effects of the forest environment on hypertensive individuals is lacking. This study provides scientific evidence suggesting that a brief forest walk affects autonomic nervous system activity in middle-aged hypertensive individuals. Twenty participants (58.0 +/- 10.6 years) were instructed to walk predetermined courses in forest and urban environments (as control). Course length (17-min walk), walking speed, and energy expenditure were equal between the forest and urban environments to clarify the effects of each environment. Heart rate variability (HRV) and heart rate were used to quantify physiological responses. The modified semantic differential method and Profile of Mood States were used to determine psychological responses. The natural logarithm of the high-frequency component of HRV was significantly higher and heart rate was significantly lower when participants walked in the forest than when they walked in the urban environment. The questionnaire results indicated that, compared with the urban environment, walking in the forest increased "comfortable", "relaxed", "natural" and "vigorous" feelings and decreased "tension-anxiety," "depression," "anxiety-hostility," "fatigue" and "confusion". A brief walk in the forest elicited physiological and psychological relaxation effects on middle-aged hypertensive individuals.

©,Several million years have passed since a subset of primates became humans. Because we spent more than<br /> 99.99% of our evolutionary history in natural environment, it is considered that we are essentially adaptive to nature.<br /> However, we live in a society characterized by urbanization and artificiality despite our physiological functions still<br /> being adapted to a natural environment. According to the concept of evidence-based medicine, we reviewed preventive<br /> medical effects of nature therapy, which comprised forest, park, wood, and flower therapy. We collected scientific<br /> data from field and laboratory experiments using physiological indicators. We expect nature therapy to play an<br /> increasingly important role in preventive medicine in the future.

Despite an increasing attention and public preference for rural amenities, little evidence is available on the health benefits of a rural environment. In this study, we identified physiological and psychological benefits of exposure to a rural environment using multiparametric methods. Twelve young male adults participated in a 3-day field experiment (mean +/- standard deviation age, 22.3 +/- 1.3 years). Sleeping environment, diet program, physical activities, and other factors possibly affecting physiological responses were controlled during experiment period. For all participants, salivary cortisol concentration, heart rate variability, and blood pressure were measured at rural and urban field sites. Self-evaluation questionnaires were administered to analyze the psychological states in two different environments. Volatile compounds in the air were also analyzed to investigate air quality. The data were compared between rural and urban environments. The data showed that exposure to a rural environment reduced stress hormone secretion and sympathetic nervous activity and increased parasympathetic nervous activity. Short-term exposure to a rural environment also improved mood states. Our findings indicate that exposure to a rural environment effectively reduced physiological stress and enhanced psychological well-being.

OBJECTIVES: To examine the psychological effects of forest therapy program on workers.METHODS: The subjective symptoms index, a shortened version of the profile of mood states (POMS), and a semantic differential (SD) method were used to measure the psychological effects.RESULTS: The evaluations were performed 3 days before, during, and 1, 3, and 5 days after the forest therapy. The following results were obtained: (1) the subjective symptoms improved before breakfast and continued for 5 days; (2) the mood evaluated using POMS improved before breakfast and continued for 3 days; and (3) “comfortable,” “relaxed,” and “natural” feelings evaluated using the SD method were enhanced before breakfast, lunch, and dinner during forest therapy.CONCLUSIONS: These results provided scientific evidence of the psychological effects of forest therapy program on workers.

BACKGROUND AND PURPOSE Natural scenes like forests and flowers evoke neurophysiological responses that can suppress anxiety and relieve stress. We examined whether images of natural objects can elicit neural responses similar to those evoked by real objects by comparing the activation of the prefrontal cortex during presentation of real foliage plants with a projected image of the same foliage plants. METHODS Oxy-hemoglobin concentrations in the prefrontal cortex were measured using time-resolved near-infrared spectroscopy while the subjects viewed the real plants or a projected image of the same plants. RESULTS Compared with a projected image of foliage plants, viewing the actual foliage plants significantly increased oxy-hemoglobin concentrations in the prefrontal cortex. However, using the modified semantic differential method, subjective emotional response ratings ("comfortable vs. uncomfortable" and "relaxed vs. awakening") were similar for both stimuli. CONCLUSIONS The frontal cortex responded differently to presentation of actual plants compared with images of these plants even when the subjective emotional response was similar. These results may help explain the physical and mental health benefits of urban, domestic, and workplace foliage.

Autonomic responses to urban and forest environments were studied in 625 young male subjects. The experimental sites were 57 forests and 57 urban areas across Japan. The subjects viewed the landscape (forest or urban environment) for a period of 15 min while sitting on a chair. During this period, heart rate variability (HRV) was monitored continuously. The results were presented as histograms and analyzed with special reference to individual variations. Approximately 80% of the subjects showed an increase in the parasympathetic indicator of HRV (lnHF), whereas the remaining subjects showed a decrease in the parasympathetic activity. Similarly, 64.0% of the subjects exhibited decreases in the sympathetic indicator of HRV (ln[LF/HF]), whereas the remaining subjects showed opposite responses. Analysis of the distribution of HRV indices (lnHF and ln[LF/HF]) demonstrated the effect of forest environments on autonomic activity more specifically than the conventional analysis based on the difference in mean values.

Objectives: People have been aware of essential oils, which are derived from plants, for a long time. Recently, we have become interested in physiological and subjective effects of daily exposure to essential oils. The primary aim of the present study was to clarify effects of olfactory stimulation with rose or orange oil on prefrontal cortex activity; subjective evaluations of relaxation were also determined. Setting and interventions: Subjects were exposed for 90s to air impregnated with either rose or orange essential oil. As a control, subjects wore the same device but inhaled only unimpregnated air. The three stimuli were randomly presented to each subject. Main outcome measures: Physiological effects were determined by near-infrared time-resolved spectroscopy and a modified semantic differential approach was used to determine subjective evaluations. Results: The study participants were 20 female university students (mean age 22.5 +/- 1.6 years). Olfactory stimulation by rose or orange oil induced: (1) a significant decrease in oxyhemoglobin concentration in the right prefrontal cortex and (2) an increase in "comfortable," "relaxed," and "natural" feelings. Conclusion: These findings indicate that olfactory stimulation by rose or orange oil induces physiological and psychological relaxation. (C) 2014 Elsevier Ltd. All rights reserved.

Empirical evidence suggests that three-dimensional (3D) images of nature promote physiological relaxation in humans by providing more realistic effects compared with two-dimensional (2D) images. However, no studies have evaluated the physiological relaxation effects of nature-derived 3D images on prefrontal cortex and autonomic nerve activity. The present study aimed to clarify the physiological relaxation effects of visual stimulation by 3D flower images on prefrontal cortex and autonomic nerve activity. Nineteen male university students (22.2 +/- 0.6 years) were presented with 3D and 2D images of the water lily for 90 s. Prefrontal cortex activity was measured using near-infrared spectroscopy, while autonomic nerve activity was measured using heart rate variability (HRV). Psychological effects were determined using a modified semantic differential method (SD). Compared with visual stimulation by 2D images, that by 3D images resulted in a significant decrease in oxyhemoglobin concentration in the right prefrontal cortex, lower sympathetic activity as calculated by the ratio of the low-frequency to high-frequency HRV component, and a significantly greater realistic feeling as evidenced by higher SD ratings. In conclusion, visual stimulation by realistic 3D floral images promotes physiological relaxation more effectively than the corresponding 2D image.

Objective: To clarify the effect of olfactory stimulation by fresh rose flowers, which exude a strong fragrance, on heart rate variability. Settings: A chamber with an artificial climate maintained at 25 degrees C with 50% relative humidity and 230 lux illumination at the Center for Environment, Health, and Field Sciences, Chiba University, Japan. Participants: Nineteen female university and graduate students (mean age, 21.6 +/- 1.5 years; age range, 19.0-26.0 years). Interventions: Fresh rose flowers as an olfactory stimulant, with air as a control. Outcome measures: Heart rate variability and subjective evaluations. The power levels of the high-frequency (HF) (0.15-0.40 Hz) and low-frequency (LF) (0.04-0.15 Hz) components of heart rate variability were calculated by the maximum-entropy method. The HF power was considered to reflect parasympathetic nervous activity. The LF/HF power ratio was determined to reflect the sympathetic nervous activity. A modified semantic differential method was used to perform subjective evaluations. Results: Fresh rose flowers induced (1) a significant increase in parasympathetic nervous activities and (2) an increase in "comfortable'' and "natural'' feelings. Conclusion: The findings indicated that olfactory stimulation by fresh rose flowers induced physiological and psychological relaxation.

Objectives: To clarify the effect of olfactory stimulation with perilla essential oil on human prefrontal cortex activity using near-infrared time-resolved spectroscopy. Design: Single-center prospective study. Methods: Nineteen female university students (mean age, 21.6 +/- 1.5 years) participated in the study. Perilla essential oil was used as an olfactory stimulant and air as a control. Oxyhemoglobin concentrations in the prefrontal cortex were measured by using near-infrared time-resolved spectroscopy when the participants were presented with the stimulant or control. Emotional effects were subjectively evaluated by using a modified semantic differential method. Results: Olfactory stimulation with the perilla essential oil significantly reduced the oxyhemoglobin concentration in the prefrontal cortex. No significant differences in the feelings of comfort or relaxation, which strongly reflect human mental status, were observed between the perilla essential oil and control periods. Conclusions: Olfactory stimulation with perilla essential oil reduced prefrontal cortex activity, thereby inducing physiologic relaxation.

The present study investigated the well-being effects of short-term forest walking and viewing ("forest bathing"). The hypothesis in our study was that both environment (forest vs. urban) and activity (walking and viewing) would influence psychological outcomes. An additional aim was to enhance basic research using several psychological methods. We conducted the experiments using 45 respondents in four areas of Japan from August to September, 2011. The hypothesis in our study was supported, because significant interaction terms between the environment and activity were confirmed regarding the Profile of Mood States (POMS) indexes, Restorative Outcome Scale (ROS) and Subjective Vitality Scale (SVS). No statistical differences between the two experimental groups in any of the ten scales were found before the experiment. However, feelings of vigor and positive effects, as well as feelings of subjective recovery and vitality were stronger in the forest environment than in the urban environment.

©,The interests in promotion of health and well-being through gardening activities are high. This article reviewed the psychological and psychological effects of gardening activities from domestic and foreign precedent studies. Although mental and physical health improvements due to gardening activities were reported, this review shows that most measurements are based on a subjective estimation or an interview. There were extremely few accumulations of data based on scientific evidence. Therefore, the importance of physiological evaluation made from a future preventive medical viewpoint was highlighted.

Background: It is widely believed that contact with the natural environment can improve physical and mental health. Urban green spaces may provide city residents with these benefits; however, there is a lack of empirical field research on the health benefits of urban parks. Methods: This field experiment was performed in May. Seventeen males aged 21.2 +/- 1.7 years (mean +/- standard deviation) were instructed to walk predetermined 15-minute courses in an urban park and a nearby city area (control). Heart rate and heart rate variability (HRV) were measured to assess physiological responses. The semantic differential (SD) method, Profile of Mood States (POMS), and State-Trait Anxiety Inventory (STAI) were used to measure psychological responses. Results: Heart rate was significantly lower while walking in the urban park than while walking in the city street. Furthermore, the urban park walk led to higher parasympathetic nervous activity and lower sympathetic nervous activity compared with the walk through the city street. Subjective evaluations were generally in accordance with physiological reactions, and significantly higher scores were observed for the 'comfortable', 'natural', and 'relaxed' parameters following the urban park walk. After the urban park walk, the score for the 'vigor' subscale of the POMS was significantly higher, whereas that for negative feelings such as 'tension-anxiety' and 'fatigue' was significantly lower. The score for the anxiety dimension of the STAI was also significantly lower after the urban park walk. Conclusions: Physiological and psychological results from this field experiment provide evidence for the physiological and psychological benefits of urban green spaces. A brief spring-time walk in an urban park shifted sympathetic/parasympathetic balance and improved mood state.

Background: In recent years, the physiological relaxing effect brought by nature is becoming clear; however, many workers find it difficult to be exposed to nature in their working environment. Exposure to fresh flowers represents an opportunity to incorporate nature into their working lives. In this study, we examined the effects of exposure to roses on physiological and psychological variables (heart rate variability, pulse rate, and subjective responses) in office workers. Results: The experimental site was Mizuho Information & Research Institute, Inc., in the Tokyo metropolitan area. Thirty-one male office workers were included in the present study. The subjects were exposed to thirty unscented pink roses (Rosa, Dekora) arranged in a cylindrical glass vase for 4 min. In the control condition, the subjects were not exposed to flowers. After the experiments, the subjects completed a questionnaire. The order of exposure was counterbalanced among subjects. Among subjects exposed to roses, the high-frequency component of heart rate variability was significantly higher than in controls. Similarly, `comfortable,' `relaxed' and `natural' feelings were more common in subjects exposed to roses. Conclusions: Data from this study support the presence of physiological and psychological relaxing effects of being exposed to flowers on office workers.

There has been growing attention on the effects of forest on physiological relaxation and immune recovery, particularly in forest medicine research, from a perspective of preventive medicine. Japan is a world leader in the accumulation of scientific data on forest medicine research. In this review, we summarize the research that has been conducted in this area since 1992. We conducted field experiment, involving 420 subjects at 35 different forests throughout Japan. After sitting in natural surroundings, these subjects showed decrease in the following physiological parameters compared with those in an urban control group: 12.4% decrease in the cortisol level, 7.0% decrease in sympathetic nervous activity, 1.4% decrease in systolic blood pressure, and 5.8% decrease in heart rate. This demonstrates that stressful states can be relieved by forest therapy. In addition, it should be noted that parasympathetic nervous activity was enhanced by 55.0%, indicating a relaxed state. The results of walking experiments provided similar results. Li et al. demonstrated that immune function was enhanced by forest therapy in middle-aged employees who volunteered to participate in these experiments. Natural killer cell activity, an indicator of immune function, was enhanced by 56% on the second day and returned to normal levels. A significant increase of 23% was maintained for 1 month even after returning to urban life, clearly illustrating the preventive benefits of forest therapy. In an indoor room experiment, we conducted tests with the following: 1) olfactory stimulation using wood smell, 2) tactile stimulation using wood, and 3) auditory stimulation using forest sounds. These indoor stimulations also decreased the blood pressure and pulse rate, and induced a physiological relaxation effect. We anticipate that forest medicine will play an increasingly important role in preventive medicine in the future.

OBJECTIVES: To clarify the physiological and psychological effects of a one-day forest therapy.METHODS: The experiments were conducted at three sites, each containing a forest area and an urban area in Japan. Twelve male students participated at each of the three venues (total, 36 subjects). The subjects were randomly assigned to visit either the forest or urban area and were instructed to view the scenery in a seated position for 15 min. Heart rate variability and heart rate were measured to assess physiological response. The semantic differential method, reports of &quot;refreshed&quot; feeling, &quot;state anxiety&quot; in the State-Trait Anxiety Inventory (STAI) and Profile of Mood States (POMS) were used to determine psychological responses.RESULTS: Physiological data revealed that the subjects demonstrated significantly different responses to the forest and urban environments. For heart rate variability, the subjects showed a significantly higher ln(HF) and a lower ln(LF/HF) in the forest environment than in the urban environment. Heart rate decreased in the forest environment relative to that in the urban environment. The forest environment was perceived as significantly more &quot;comfortable,&quot; &quot;soothing,&quot; and &quot;natural&quot; than the urban environment after viewing. The score for &quot;refreshed&quot; feeling was also significantly higher. The score for the &quot;state anxiety&quot; in STAI was significantly reduced by viewing the scenery in the forested areas. The score for the &quot;vigor&quot; subscale of the POMS was significantly improved by viewing the scenery in the forested areas, whereas scores for negative feelings, such as &quot;tension-anxiety&quot; and &quot;fatigue,&quot; were significantly reduced.CONCLUSIONS: These results provided scientific evidence of the physiological and psychological effects of a one-day forest therapy.

OBJECTIVE: To provide scientific evidence of the physiological and psychological effects of forest and urban environments on 47 young male adults undergoing stay-in forest therapy.METHODS: Field experiments were conducted at four sites in Japan. At each site, 12 subjects participated in the experiment. The experiments were conducted in forest and urban environments, and the subjects&#039; physiological and psychological responses to these environments were compared. On the first day, six subjects were sent to a forest area, and the other six were sent to an urban area as controls. The groups were switched the next day. Heart rate variability and heart rate were measured to assess physiological responses. The semantic differential method for assessing emotions, the reports of &quot;refreshed&quot; feeling, and the Profile of Mood States (POMS) were used to assess psychological responses. The physiological and psychological responses of each subject were recorded during and after walking, and the differences in indices were compared between the two environments.RESULTS: The forest environment was associated with a higher parasympathetic nervous activity, a lower sympathetic nervous activity, and a lower heart rate than the urban environment. The subjective evaluation scores were generally in accordance with the physiological reactions and were significantly higher in the forest environment than in the urban environment. POMS measurements showed that the forest environment was psychologically relaxing and enhanced psychological vigor.CONCLUSIONS: This study provided clear scientific evidence of the physiological effects of forest therapy. The results will contribute to the development of forest therapy research and support the inclusion of forest therapy in preventive medicine.

OBJECTIVES: The aim of this study was to elucidate the physiological adjustment effect of forest therapy based on the Law of Initial Value.METHODS: The experiments were conducted in nine forest and urban areas in Japan during the period from 2011 to 2012. There were 12 male Japanese university students participating in each of the nine experiments (total, 108 participants). Of these, 98 subjects (mean age ± standard deviation, 21.4 ± 1.6 years) were analyzed. The subjects were instructed to view a real forest landscape or urban area for 15 min. The systolic blood pressure, diastolic blood pressure, and pulse rate of each subject were measured. We analyzed the correlation between the initial values (after city viewing) and the differences in values between the two environments (after forest viewing-after city viewing).RESULTS: There was a negative correlation between the initial values and the differences in values between the two environments. The subjects whose initial systolic blood pressure, diastolic blood pressure, and pulse rate were high showed marked decreases in these parameters as their response after viewing the forest environment, whereas those whose initial systolic blood pressure, diastolic blood pressure, and pulse rate were low showed increases in these parameters as their response.CONCLUSIONS: These results support the premise that the physiological effect of a forest environment can differ depending on a subject&#039;s initial response values. Moreover, it was clear that forest therapy caused physiological adjustment, normalizing blood pressure and pulse rate.

© 2014 University of Florence. All rights reserved.Although D-Limonene can be considered an important component of nature-based stimuli, the physiological effects of olfactory stimulation with D-Limonene have not been completely clarified by scientific studies. The physiological and psychological effects of olfactory stimulation with D-Limonene were studied measuring heart rate variability (HRV), heart rate, and subjective evaluation using a modified semantic differential method; thirteen Japanese female university students (mean age±SD, 21.5±1.0 years) participated in the study. A concentration of 60 μL of D-Limonene was used as olfactory stimulant and room air as control. Subjects were exposed for 90 s while sitting with eyes closed. During D-Limonene inhalation: (1) the high-frequency (HF) value of HRV, a marker of parasympathetic nervous activity that is enhanced in relaxing situations, was significantly higher; (2) the heart rate was significantly lower; and (3) subjects reported feeling significantly more comfortable during D-Limonene administration than control. The results obtained clearly indicate that olfactory stimulation with D-Limonene induced physiological and psychological relaxation, providing important scientific evidence of the health benefits of D-Limonene.

© 2014 University of Florence. All rights reserved.With lifestyles in modern society becoming increasingly stressful, there is growing interest in the physiological relaxing effects of the natural environment. Particular interest has been paid to the physiological effects of indoor plants, however no studies have revealed the effects of such visual stimulation on minors. In this study 85 (41 male and 44 female; 16.5±0.9 years; mean±SD) students were exposed, or not as control, to a typical foliage plant, dracaena (Dracaena deremensis; Lemon Lime), for 3 min. Physiological indices included heart rate variability (HRV) and pulse rate, using an accelerated plethysmography at the fingertip, were collected continuously during the experiments. The results indicated that the high frequency component (HF), a general index of parasympathetic nervous activity, was significantly higher; the low frequency component [LF/(LF+HF)], a general index of sympathetic nervous activity, was significantly lower; and the pulse rate was significantly lower. After exposure, or not, the subjects completed a questionnaire as psychological evaluation. A 13-point rating scale was used for following parameters: “comfortable-uncomfortable,” “relaxed-awakening,” and “natural-artificial.” Results of the study showed that subjects felt more comfortable, relaxed and natural after visualizing the dracaena plants. Overall, the physiological and psychological relaxing effects of visual stimulation with foliage plants in high school students is confirmed.

© 2014, University of Florence. All rights reserved.This study was conducted to clarify the physiological and psychological effects of the odor of orange essential oil in humans. Thirteen healthy male university students (mean age 23.0±1.1 years) participated. The study was conducted in an artificial climate chamber with temperature 24°C, relative humidity 50%, and illumination 50 lux. The subjects randomly inhaled orange essential oil for 120 s. Fresh air inhalation was used as the control condition. Heart rate variability (HRV), blood pressure, and pulse rate were continuously measured before (resting time) and during inhalation of the experimental odor. In addition, sensory evaluation and subjective odor intensity were evaluated after inhalation. The high frequency component of HRV was significantly higher, systolic and diastolic blood pressure was significantly lower, and the subjective “feeling of comfort” was significantly greater during inhalation of the orange essential oil than during inhalation of fresh air. These findings indicate that inhalation of orange essential oil effectively induces relaxation in humans.

Background. Despite increasing attention toward forest therapy as an alternative medicine, very little evidence continues to be available on its therapeutic effects. Therefore, this study was focused on elucidating the health benefits of forest walking on cardiovascular reactivity. Methods. Within-group comparisons were used to examine the cardiovascular responses to walking in forest and urban environments. Forty-eight young adult males participated in the two-day field research. Changes in heart rate variability, heart rate, and blood pressure were measured to understand cardiovascular reactivity. Four different questionnaires were used to investigate the changes in psychological states after walking activities. Results. Forest walking significantly increased the values of ln(HF) and significantly decreased the values of ln(LF/HF) compared with the urban walking. Heart rate during forest walking was significantly lower than that in the control. Questionnaire results showed that negative mood states and anxiety levels decreased significantly by forest walking compared with urban walking. Conclusion. Walking in the forest environment may promote cardiovascular relaxation by facilitating the parasympathetic nervous system and by suppressing the sympathetic nervous system. In addition, forest therapy may be effective for reducing negative psychological symptoms.

The present study aimed to clarify the relationship between psychological responses to forest and urban environmental settings and the physical variables that characterize these environments, by examining the psychological responses of 168 subjects to their physical environment. Field experiments were conducted in 14 forests and 14 urban areas across Japan. The semantic differential (SD) method was employed in which a questionnaire was administered to subjects prior to their walks in the forests and urban areas. In addition, the profile of mood states (POMS) questionnaire was administered before and after the walks, as well as before and after they sat and viewed the forest and urban landscapes. The environmental variables measured were air temperature, relative humidity, radiant heat, wind velocity, and two indices of thermal comfort [predicted mean vote (PMV) and predicted percentage dissatisfied (PPD)]. Responses to the SD questionnaire indicated that compared to urban settings, forest settings are perceived as being significantly more enjoyable, friendly, natural, and sacred. The POMS measures of tension and anxiety (T-A), depression and dejection (D), anger and hostility (A-H), vigor (V), confusion (C), fatigue (F), and total mood disturbance (TMD) showed significant differences between the forests and urban areas. These results strongly support the suggestion that forest settings have attention restoration effects. The psychological responses to physical environments were also significantly related to air temperature, relative humidity, radiant heat, wind velocity, PMV, and PPD. The results of this study might be useful in designing restoration environments in urban areas. © 2013 by Nova Science Publishers, Inc. All rights reserved.

©2013, Rapid urbanization and artificialization have caused environmental changes that threaten human health and<br /> quality of life. However, there is a lack of evidence-based research focused on the physiological and psychological<br /> impacts of urban environments. The aim of this study was to clarify the physiological and psychological impacts of<br /> urban environments using a field experiment. Thirty-six Japanese male university students (mean age 22.1 ± 1.8<br /> years) participated in the study, each was instructed to walk a predetermined 13-min course in an urban area (test)<br /> and forested area (control). Heart rate and heart rate variability were measured to assess physiological responses<br /> to the environment. The semantic differential method for assessing emotions and reports of feeling “refreshed” were<br /> used to determine psychological responses. Heart rate was significantly higher and the high-frequency component of<br /> heart rate variability, which is an index of parasympathetic nervous activity that is enhanced in relaxing situations, was<br /> significantly lower when the subjects walked through urban than through forested areas. Moreover, the psychological<br /> indices showed that the subjects felt more artificial and less “refreshed” when walking in the urban areas. In conclusion,<br /> these findings provide important scientific evidence of physiological and psychological impacts of walking stress in<br /> urban environments.

©2013, The purpose of this study was to investigate the effect of thermal environment of forest and grass area<br /> in arboretum on human physiological response. And the purpose of this paper is to scientifically proved that thermal<br /> comfort of forest. Twenty-one healthy men and women in their twenties (23.3±1.6) participated as subjects.<br /> Measurements were taken, while the subjects sat in forest and grass area for five minutes, wearing eye masks to<br /> control visual stimulation.<br /> Predicted mean vote(PMV) and predicted percentage of dissatisfied(PPD) were measured as thermal<br /> environment indicators, and heart rate(HR) and heart rate variability(HRV) were measured as physiological<br /> indicators. PMV and PPD of forest were found to be significantly lower than those of grass area. As for physiological<br /> response, HR and LF/HF of both physiological indicators were lower, while HF of HRV was higher in forest,compared to grass area, to a significantly degree. Base on the findings, it could be concluded that forest has more<br /> pleasant thermal conditions than grass area. And it was able to prove that thermal comfort was influenced to human<br /> physiological response.

Background: Despite increasing attention and a growing volume of research data, little physiological evidence is available on the benefits of horticultural activity and the different effects on individuals. Therefore, the aim of the present study was to investigate the physiological effects of horticultural activity and to examine how differences in personality alter these effects. Results: The effects of transplanting real flowers (horticultural activity) and handling artificial flowers (control activity) on human physiological activity were compared. On the first day, eight participants engaged in horticultural activity and another eight in the control activity. On the second day, participants switched roles. Participants' physiological conditions during each activity were assessed by measuring the heart rate and heart rate variability (HRV). Psychological responses, which were measured using a semantic differential rating scale, showed that the horticultural activity promoted comfortable, soothed, and natural feelings, compared to the control activity. Analysis of physiological responses using two-way repeated measures analysis of variance (ANOVA) revealed that sympathetic nervous activity significantly decreased in the late time period (11 to 15 minutes) of horticultural activity only in the type A group. Conclusions: This study supports the fact that the horticultural activity can enhance psychological and physiological relaxation effects, although these physiological effects can differ among individuals with different personalities. © 2013 Lee et al. licensee BioMed Central Ltd.

Background: In recent years, the physiological relaxation effects of natural environments have been widely exploited, and although individual differences in the effects of forest therapy are known, assessment methods have not been clearly established. This study used a classification based on Type A and Type B behavior patterns to explain individual differences in physiological responses to forest environments. Methods: We performed physiological experiments in 44 forest and urban (controls) areas. In total, 485 male university students (age, 21.8 +/- 1.6 years) participated in the study. The subjects were asked to visit forest or urban environments randomly and observe each landscape for 15 min. The subjects' pulse rates and blood pressures were tested to evaluate their physiological responses. The Kwansei Gakuin daily life questionnaire was used to identify Type A and Type B behavior patterns in subjects. Results: The pulse rate was significantly lower in the Type B group after exposure to forest areas than after exposure to urban areas, whereas no significant difference was observed in the Type A group. In addition, the pulse rate was significantly lower in the low scoring subjects in the Type B group, which was consistent with changes in their diastolic blood pressure. Conclusions: These results suggest that individual differences in pulse rate and blood pressure in response to forest environments can be explained by Type A and Type B behavior patterns.

Background: Interaction with nature has a relaxing effect on humans. Increasing attention has been focused on the therapeutic effects of urban green space; however, there is a lack of evidence-based field research. This study provided scientific evidence supporting the physiological and psychological effects of walking on young males in urban parks in winter. Findings: Subjects (13 males aged 22.5 +/- 3.1 years) were instructed to walk predetermined 15-minute courses in an urban park (test) and in the city area (control). Heart rate and heart rate variability (HRV) were measured to assess physiological responses. The semantic differential (SD) method, Profile of Mood States (POMS), and State-Trait Anxiety Inventory (STAI) were used to determine psychological responses. Heart rate was significantly lower and the natural logarithm of the high frequency component of HRV was significantly higher when walking through the urban park than through the city area. The results of three questionnaires indicated that walking in the urban park improved mood and decreased negative feelings and anxiety. Conclusions: Physiological and psychological data from this field experiment provide important scientific evidence regarding the health benefits of walking in an urban park. The results support the premise that walking in an urban park has relaxing effects even in winter.

This study aims at clarifying the physiological relaxing effect which pink rose brings about for 55 high school students. The stimulation was made by 30 pink roses with non-scent arranged in a vase while the control had no flower for 4 minutes. The physiological indices were the heart rate variability and pulse rate which employed fingertip accelerated plethysmography, and the psychological indicators were the SD method and the shortened version of profile of mood states (POMS). The results as follow: (1) HF were significantly higher, and LF/HF were significantly lower, (2) &quot;comfortable&quot;, &quot;natural&quot;, and &quot;relaxed&quot; feelings and the mood state were significantly better, while viewing fresh rose flowers than control.

The present study investigated the physiological and psychological effects of viewing urban forest landscapes on 48 young male urban residents. Four forested areas and four urban areas located in central and western Japan were used as the test sites. We found that in the forested areas, the subjects exhibited (i) significantly lower diastolic blood pressure, (ii) significantly higher parasympathetic nervous activity, but significantly lower sympathetic nervous activity, and (iii) significantly lower heart rate. The forest landscapes (iv) obtained better scores in subjective ratings, and (v) induced significantly less negative and more vigorous moods. Taken as whole, these findings suggest that even a short-term viewing of forests has relaxing effects. We have thus concluded that the approach taken in this study is useful in exploring the influences of urban green space on humans, as well as contributing to the planning and design of a healthy environment for urban residents. © 2013 Elsevier B.V.