Quantitative Research on the Perception Mechanism of Outdoor Landscape Spaces in High-rise Buildings

LIU Binyi,(Egypt) Mohamed Elsadek

The emergence of high-rise architectural clusters has introduced a paradigm shift within modern urban landscapes,giving birth to a novel entity -high-rise landscapes.These elevated living environments usher in a realm of unprecedented opportunities and challenges for human well-being.The allure of elevated vantage points,offering panoramic vistas reminiscent of "overlooking mountains and rivers at dawn",juxtaposes the sobering realities of limited green spaces and outdoor amenities.Yet,despite their burgeoning presence in urban settings,our comprehension of the multifaceted impact of high-rise landscapes on human health remains in its nascent stages.

In our quest for knowledge,we meticulously utilized three distinct visual stimuli to represent urban spaces,green areas,and water features.A drone positioned at an altitude of 120 meters captured three photographs showcasing these diverse environments.These aerial shots were taken at Gongqing Forest Park (Fig.3) in the Yangpu District of Shanghai.This park stands as the city's secondlargest park and is situated in the northern part of Shanghai.For this study,we enrolled a cohort of twenty healthy university students,with an average age of 22 years.These participants were divided into three groups,with each group assigned to view one of the three visual stimuli: urban space,green space,or water space.Detailed instructions were provided,emphasizing the importance of observing and appreciating the scenery of the designated environment.

These carefully selected stimuli were instrumental in our meticulous investigation of concealed arousal indicators.To this end,we employed precision instruments such as electroencephalography (EEG),heart rate variability measurements,and skin conductance.Simultaneously,we delved into the emotional status of the human psyche by employing an enhanced semantic differential questionnaire.The primary objective of this research was to unravel the intricate narrative linking high-rise urban landscapes to human well-being,thereby paving the way for further scholarly exploration and the generation of valuable insights.

1 Landscape Perception in High-rise Environments

The relentless surge of urbanization is exacting a toll on natural habitats and green spaces,leading to an escalation in the prevalence of non-communicable diseases and psychological disorders.This burden is particularly heavy for marginalized communities,which face restricted access to outdoor environments,rendering them vulnerable to various health afflictions.In response to this pressing issue,high-rise buildings have emerged as the predominant architectural archetype in urban regions worldwide.Nevertheless,these soaring structures present formidable challenges,primarily the noticeable absence of greenery and vegetation,contributing to elevated stress levels and deteriorating mental health among their occupants.As urban spaces continue to grow vertically and intensify in population density,the integration of nature into the urban fabric becomes an urgent necessity.

The perception of landscapes from high-rise buildings has gained increasing significance in the context of rapid urbanization.Green spaces have been associated with a range of benefits,including stress reduction and enhancements in mental wellbeing.This study seeks to investigate the potential advantages of incorporating nature into the design of high-rise buildings.

The quality of window views in high-rise buildings plays a crucial role in shaping human perception and overall well-being.Views of greenery and natural elements have been linked to reduced psychological distress and improvements in emotional states.While high-rise buildings offer a unique perspective on the surrounding environment,the design and accessibility of such views can significantly impact landscape perception.This paper underscores the importance of window views in high-rise building design and their profound influence on human perception,mental health,and overall well-being.

2 Physiological Responses to Different Landscapes from a High-rise

2.1 Electroencephalographic response: "Alpha relative power variability in AF3 and AF4 electrodes was observed while viewing the images of the building,green space,and water"

In our analysis,we conducted a comparison of the average alpha relative power,focusing on two electrodes,AF3 and AF4,as depicted in Fig.7.Our results revealed significant variations in alpha relative power during the viewing of different visual stimuli.For the AF3 channel,we observed noteworthy disparities between the building image and green space (P=0.001),as well as between buildings and water space (P=0.001).Furthermore,we found a significant difference between the alpha relative power during visual stimulation by green space and water space images (P=0.01).

Turning to the AF4 channel,we identified significant distinctions between buildings and green space (P=0.05),as well as between buildings and water space (P=0.001).In contrast to the AF3 channel,we did not observe significant differences between green space and water space images in terms of alpha relative power (P=0.1).These findings suggest that both green and water space images contributed to increased participant relaxation.Additionally,both images generated significant emotional responses in the prefrontal lobe compared to viewing buildings,as evidenced by higher alpha relative power.

Our results indicate that the observation of green and water spaces from a high vantage point has distinct effects on cerebral functioning compared to viewing urban buildings.Participants consistently exhibited higher alpha wave amplitudes when exposed to green space and water space images,which are known to induce a sense of calm and relaxation.Nevertheless,our findings demonstrated unique patterns in physiological and psychological responses to these different visual stimuli.In contrast,exposure to urban images led to specific physiological changes,possibly attributed to the inherent characteristics of urban settings,such as high density,structural complexity,and limited presence of natural elements.

Our analysis of prefrontal alpha waves unveiled a significant increase in alpha relative power among participants who viewed green and water spaces from a height of 120 meters.This aligns with previous research and supports prior findings indicating that greater green coverage from a lower height induces stronger alpha rhythms associated with relaxation.The heightened alpha wave activity suggests potential benefits in terms of cognitive and emotional well-being.Increased alpha waves have been linked to improved creativity and reduced depressive symptoms,emphasizing the potential advantages of incorporating green and water spaces in high-rise environments.

These findings underscore the importance of integrating natural elements within urban spaces to enhance the well-being of residents.Moreover,visual exposure to green or water space from a 120-meter elevation was associated with an increase in alpha power,signifying a reduction in depressive symptoms and an enhanced sense of calmness.This is consistent with previous research demonstrating the positive emotional and psychological effects of viewing natural elements,further emphasizing the value of incorporating green and water spaces within high-rise environments.

2.2 Heart rate variability responses

2.2.1 Natural logarithm of high-frequency heart rate variability during a 3-minute observation of urban,green,and water spaces

Fig.8 illustrates the aggregate high-frequency(HF) values,reflecting parasympathetic nervous system activity,in response to participants'observations of building,green,and water space images.When participants viewed green space and water space images,there was a marked increase in HF values compared to their observations of building images.Notably,no significant difference was observed in HF values between the visual stimuli featuring green space and water space images.This points to a substantial increase in parasympathetic nervous activity when viewing green space and water space images in contrast to building images.

2.2.2 Analysis of LF/HF ratio during a 3-minute observation of urban,green,and water spaces

Conversely,the low-frequency/high-frequency(LF/HF) values for the building image were significantly higher than for both the green space and water space images.However,there were no significant differences in LF/HF values between the two types of natural stimuli.This indicates that a state of relaxation was more pronounced when participants viewed green space and water space images in comparison to building images.

In line with our prior research,this study offers compelling evidence regarding the impact of visual exposure to green space or water space from a height of 120 meters on autonomic nervous system activity.More specifically,we observed a significant increase in parasympathetic nerve activity,reflecting relaxation,and a concurrent decrease in sympathetic nervous activity,indicative of a reduced stress response,when participants viewed green space and water space images as opposed to urban images.These physiological changes were assessed through heart rate variability(HRV),a well-established measure of sympathetic and parasympathetic nervous system dynamics associated with stress,anxiety,relaxation,and calmness.

2.3 Participants' mean skin conductance during a 3-minute observation of urban,green,and water spaces

In Fig.10,we present the graphical representation of participants' average skin conductance over the 3-minute observational period.Notably,there was a slight variation in skin conductance when participants were exposed to different visual stimuli.While skin conductance appeared slightly higher when participants viewed building images compared to green and water spaces,these differences did not reach statistical significance.

3 Physiological Responses to Different Landscapes

Fig.11 provides an overview of the results stemming from the assessment of impressions after participants viewed urban,green space,and water space images using three opposing adjective pairs.In the evaluation of comfort level,both the green space and water space images garnered high scores,indicating that they were perceived as comfortable.In stark contrast,the building image received a significantly lower score,indicating discomfort.This underscores that viewing green space and water space from a high-rise setting left a notably more comfortable impression than viewing the urban building image.For the relaxed-awakening evaluation,the green space and water space images were rated as inducing relaxation,whereas the building image was associated with a slight awakening effect.This difference in the impressions was significant.Additionally,participants reported more relaxed feelings when viewing the green space image,signifying a distinct psychological response.

In the evaluation of the natural-artificial impression,the green space and water space images were seen as highly natural,while the building image was considered artificial.The disparity among these impressions was also significant.It is evident that viewing the green space and water space images had a psychological impact associated with comfort,relaxation,and a perception of naturalness in comparison to viewing the building image.The employment of the modified Semantic Differential(SD) method revealed that participants experienced greater comfort,relaxation,and a stronger connection to nature when viewing green space and water space images compared to urban space.Thus,visual exposure to green space and water space from a height of 120 meters elicited feelings of comfort,relaxation,and a stronger sense of being in a natural environment compared to viewing urban space.These findings underscore the positive psychological impact of natural environments,particularly when integrated into high-rise settings.

4 Concluding Remarks

Our study underscores the profound human preference for natural environments over urban landscapes.The consistent enhancement of relaxation,comfort,and overall well-being when viewing natural green and water spaces from elevated perspectives holds significant implications for urban planning and architectural design.Integrating such elements into high-rise buildings offers the potential to mitigate stress levels and elevate the quality of life for residents.This research encourages the creation of healthier,more harmonious urban spaces and highlights the value of nature-based visual stimuli.

Future investigations should delve into the specific natural elements that yield the most substantial positive effects and consider the enduring impact of nature-based visual exposure on residents' well-being.The implications of our findings have the potential to shape urban planning and design practices,contributing to the development of urban environments that optimize the well-being of their inhabitants,thus fostering a brighter and more sustainable urban future.