Co-Publication

Landscapes and Human Health

William C. Sullivan & Chun-Yen Chang

http://www.mdpi.com/1660-4601/14/10/1212/htm

Key words

Landscape benefits, human health

Using functional Magnetic Resonance Imaging (fMRI) to analyze brain region activity when viewing landscapes

I-Chun Tang, Yu-Ping Tsai, Ying-Ju Lin, Jyh-Horng Chen, Chao-Hsien Hsieh, Shih-Han Hung, William C. Sullivan, Hsing-Fen Tang, & Chun-Yen Chang

Abstract

Over the years, the restorative benefits of the natural environment have been taken seriously. These restorative effects continue to be verified in research from both the psychological and physiological perspectives. The latest functional magnetic resonance imaging (fMRI) technology provides an opportunity to further explore the psychophysiological aspects of these benefits from the natural environment. This study aimed to compare the restorative value of four types of landscape environments (urban, mountain, forest, and water) through questionnaires and by investigating the relationship between the different environments and brain region activity by means of fMRI. Based on a one-way analysis of variance, a significant difference was found between the restorative value of the urban and natural environments—the most value being in the water and mountain environments and least in the urban environment. In support of this psychological result, the brain was found to respond similarly, showing increased activity in the visual and attentional focus areas when an urban environment is viewed as opposed to a natural environment. These findings reveal a new approach to test the restorative value of an environment and support the restorative effect of the natural environment.

Key words

Landscape benefits, Functional magnetic resonance imaging, Mental health, Attention restoration theory

Remotely-sensed imagery vs. eye-level photography: Evaluating associations among measurements of tree cover density

Bin Jiang, Brian Deal, HaoZhi Pan, Linda Larsen, Chung-Heng Hsieh, Chun-Yen Chang, & William C. Sullivan

Abstract

The easy availability and widespread use of remotely-sensed imagery, especially Google Earth satellite imagery, makes it simple for urban forestry professionals to assess a site and measure tree cover density without visiting the site. Remotely-sensed tree cover density has become the dominant criterion for urban forestry regulations in many countries, but it is unclear how much such measures match the eye-level tree cover density that people experience; or the information gained through site visits, eye-level photography, or from consulting with citizens. To address this uncertainty, we assessed associations among two remotely-sensed and three eye-level tree cover density measures for 140 community street sites across the Midwestern United States with low, medium, or high tree cover coverage by using linear regression analysis. We found significant associations among the two remotely-sensed measures and the three eye-level measures across the three levels of tree cover. The associations between any pair of remotely-sensed and eye-level measures, however, diminish dramatically as canopy cover increased. At high levels of canopy cover, all associations between the remotely-sensed measures and the eye-level measures became statistically insignificant. These findings suggest that measures from remotely-sensed imagery fail to represent the amount of tree cover people perceive at eye-level when canopy cover is medium or high at the site scale. Therefore, the current urban forestry planning regulations, which rely heavily on remotely-sensed tree cover density measurements, need to be revised. We suggest strategic spots where eye-level measures of tree cover density should be emphasized.

Key words

Urban forestry, Tree cover density, Remotely-sensed imagery, Eye-level photography, Association

The Effect of Biodiversity on Green Space Users’ Wellbeing—An Empirical Investigation Using Physiological Evidence

Kaowen Grace Chang, William C. Sullivan, Ying-Hsuan Lin, Wei chia Su, and Chun-Yen Chang

http://www.mdpi.com/2071-1050/8/10/1049/htm

Abstract

Promoting ecological health and human wellbeing are two fundamental goals in landscape sustainability. Green spaces are thought to improve users’ psychological and physical wellbeing through the contact with nature. However, the results of some studies that rely on self-reports suggest that when the level of naturalness in a green space reaches a certain point, the beneficial effects diminish and in some cases can cause negative responses. We explored this possibility through an experimental study in which we use physiological measures rather than perceptions to assess people’s wellbeing. We investigate how people are affected by outdoor settings with varying degrees of biodiversity and whether the correlation between biodiversity and physiological wellbeing is negative or positive. We used multiple measures of insect diversity as an indicator for biodiversity, and biofeedback measures as indicators of wellbeing. Our findings suggest that people are equally affected by more biodiverse and less biodiverse settings. Physiological responses remain largely unchanged when biodiversity increases. This suggests that settings rich in biodiversity will not negatively influence people’s physiological wellbeing, and designers and city planners should not hesitate to use ecological best practices in their designs.

Key words

Biodiversity, biofeedback, conservation, wellbeing, sustainability

Perceptual Evaluation of Natural Landscapes: The Role of the Individual Connection to Nature

I-Chun Tang, William C. Sullivan, Chun-Yen Chang

http://journals.sagepub.com/doi/abs/10.1177/0013916513520604

Abstract

Many people do not seem to have interesting perceptual experiences while in contact with nature. To identify potential antecedents of positive perceptual experiences in natural settings, we investigated the role of a personal connection to nature on perceptual evaluation of preference-related environmental information in varying natural settings. The participants (N = 77) rated three different types of images of rural forest landscapes in terms of perceived environmental information, including sense of safety, coherence, complexity, legibility, mystery, attentional restorativeness, familiarity, and preference. They also reported their personal connection to nature. The results showed that deeper personal connections to nature are associated with greater perceptual evaluations of sense of safety, legibility, mystery, and attentional restorativeness after accounting for landscape type and familiarity. A personal connection to nature is likely to enhance a person’s perceptual experiences of natural landscapes.

Key words

connection to nature, landscape perception, preference, attentional restorativeness, sense of safety

A dose of nature: Tree cover, stress reduction, and gender differences

Bin Jiang, Chun-Yen Chang, & William C. Sullivan

http://www.sciencedirect.com/science/article/pii/S0169204614001832

Abstract

Although it is well established that exposure to nearby nature can help reduce stress in individuals, the shape of the dose–response curve is entirely unclear. To establish this dose–response curve, we recruited 160 individuals for a laboratory experiment. Participants engaged in the Trier Social Stress Test (TSST) to induce psychological stress, and were then randomly assigned to view one of ten, 6-min, 3-D videos of neighborhood streets. The density of tree cover in the videos varied from 1.7% to 62.0%. We measured their stress reactions by assessing salivary cortisol and skin conductance levels. Results show a clear disparity between women and men. For women, we found no relationship between varying densities of tree cover and stress recovery. For men, the dose–response curve was an inverted-U shape: as tree cover density increased from 1.7% to 24%, stress recovery increased. Tree density between 24% to 34% resulted in no change in stress recovery. Tree densities above 34% were associated with slower recovery times. A quadratic regression using tree cover density as the independent variable and a summary stress index as the dependent variable substantiated these results [R2 = .22, F (2, 68) = 9.70, p < .001]. The implications for our understanding of the impacts of nearby nature, and for the practice of planning and landscape architecture are discussed.

Key words

Dose–response curve, Stress reduction, Salivary cortisol, Skin conductance, Tree cover density, 3-D visual media

Does awareness effect the restorative function and perception of street trees

Ying-Hsuan Lin, Chih-Chang Tsai, William C. Sullivan, Po-Ju Chang, and Chun-Yen Chang

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4133958/

Abstract

Urban streetscapes are outdoor areas in which the general public can appreciate green landscapes and engage in outdoor activities along the street. This study tested the extent to which the degree of awareness of urban street trees impacts attention restoration and perceived restorativeness. We manipulated the degree of awareness of street trees. Participants were placed into four groups and shown different images: (a) streetscapes with absolutely no trees; (b) streetscapes with flashes of trees in which participants had minimal awareness of the content; (c) streetscapes with trees; and (d) streetscapes with trees to which participants were told to pay attention. We compared the performance of 138 individuals on measures of attention and their evaluations of perceived restorativeness. Two main findings emerged. First, streetscapes with trees improved the performance of participants on attentional tests even without their awareness of the trees. Second, participants who had raised awareness of street trees performed best on the attentional test and rated the streetscapes as being more restorative. These findings enhance our knowledge about the role of an individual's awareness of restorative elements and have implications for designers and individuals who are at risk of attentional fatigue.

Key words

DSBT, attention restoration, perceived restorativeness, manipulation on awareness degree

Gaia meets Ascelpius: Creating Healthy Places

William C. Sullivan, Howard Frumkin, Richard J. Jackson, & Chun-Yen Chang

http://www.sciencedirect.com/science/article/pii/S0169204614000711?via%3Dihub

Key words

Landscape benefits, Natural environments

Mental Health and the Built Environment

William C. Sullivan, & Chun-Yen Chang

https://link.springer.com/chapter/10.5822/978-1-61091-036-1_7/fulltext.html

Key words

Built environment, Mental health, Place attachment,