Psychophysiological Effects of Bamboo Plants on Adults

Effects of Different Bamboo Forest Spaces on Psychophysiological Stress and Spatial Scale Evaluation

Forests are large-scale green space resources that may exert a positive impact on human physiology and psychology. Forests can be divided into mixed forest and pure forest, according to the number of dominant tree species. Pure forest offers specific advantages for the study of spatial structure and scale. In this study, a type of pure forest (i.e., bamboo forest) was adopted as a research object to investigate differences in the physiological and psychological responses of psychologically pressured college students to different types of forest space. We recruited 60 participants and randomly assigned them to three experimental groups: forest interior space (FIS), forest external space (FES) and forest path space (FPS). All participants were asked to perform the same pre-test task but different post-test tasks. The pre-test involved performing a pressure-inducing task, whereas the post-test involved viewing photographs of each space type. The same indicators were measured in both the pre- and post-test, including a β/α index from each lobe, positive emotion, negative emotion and total mood disturbance (TMD) values, according to the profile of mood states (POMS), in addition to spatial scale preferences obtained through a questionnaire and interviews. We analysed brain waves and mood indicators through analysis of covariance (ANCOVA), whereby the FES group exhibited the best physiological and psychological relaxation effect. The FPS group displayed a medium effect, and the FIS group exhibited the worst effect. Analysis of variance (ANOVA) was used to analyse the spatial scale scores. The FPS and FES types achieved a higher spatial scale preference scores than the FIS type. Based on a comparison of the psychophysiological results with the spatial scale preference results, spatial structure and scale are considered to be important intrinsic factors that influence the health effects of pure forest. The results can provide guidance for forest-related human health activities and their management.

Benefits of a Three-Day Bamboo Forest Therapy Session on the Physiological Responses of University Students

Studies have indicated that natural environments have the potential to improve the relationship between a stressful life and psychological well-being and physical health. Forest therapy has recently received widespread attention as a novel solution for stress recovery and health promotion. Bamboo is an important forest type in many countries, especially in East and Southeast Asia and in African countries. Bamboo is widespread throughout southwestern China. Empirical field research on the physiological effects of bamboo forest therapy is currently lacking. To explore the benefits of bamboo forest therapy on the physiological responses of university students, 120 university volunteers between the ages of 19 and 24 participated in this study (60 males and 60 females) and were randomly divided into four groups of equal size (15 males and 15 females in each). Four sites were selected for the experiment, including two natural bamboo forests (YA and YB), a bamboo forest park (DJY), and an urban environment (CS). During the testing period, all participants were asked to view the landscape for 15 min in the morning and then walk in the testing area for 15 min in the afternoon. Blood pressure (BP), heart rate (HR), and peripheral oxygen saturation (SpO2) were measured as the physiological indexes, and the semantic differential method (SDM) questionnaire was completed for the environmental satisfaction evaluation. The SDM for the subjective environmental evaluation differed significantly among the university students; they obtained a better environmental experience, in terms of sensory perception, atmosphere, climate, place, and space, in the bamboo forest sites. The three-day bamboo forest therapy session improved the physiological well-being of university students. First, the blood pressure and heart rate of the university students decreased, and the SpO2 increased, after the three-day viewing and walking activities of the three-day bamboo forest therapy session. The viewing activities had a more pronounced effect on decreased heart rate in university students. Additionally, three-day bamboo forest therapy had a positive impact on decreased systolic blood pressure and heart rate in the university students, and it was significantly decreased in females, while peripheral oxygen saturation (SpO2) remained relatively low. Finally, compared with the urban site (CS), the bamboo forest sites effectively improved the university students’ physiological state of health, decreased their physical pressure, and stabilized their physiological indicators. These findings provide scientific evidence that a three-day bamboo forest therapy session can increase positive physiological responses. The potential for a longer-term effect on human physiological health requires further investigation.

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.