Motivation and emotion/Book/2016/Stress recovery theory

Stress Recovery Theory (SRT):
What is SRT, what is the evidence, and how can it be applied?

Overview

"As long as (the simple beauty of nature) exists ... I know that then there will always be comfort for every sorrow, whatever the circumstances may be. And I firmly believe that nature brings solace in all troubles. "
Anne Frank

Prolonged exposure to urban environments can have detrimental physical and psychological effects (Moudon, 2009; Sobnqwi et al., 2004). Past research has found associations between lifetime urban environment exposure and obesity, diabetes and hypertension (Sobnqwi et al., 2004). Additionally, perceived stress from traffic noise has been associated with lower health status and depression (Moudon, 2009). It is of no surprise then that research has shown that people place a high level of importance on access to green spaces and having the ability to escape from an urban environment (Bedimo-Rung, Mowen, & Cohen, 2005; Guite, Clark, & Ackrill, 2006).

Stress Recovery Theory (SRT) provides an explanation for why natural environments are so important for human functioning, and how natural elements can aid stress recovery (Ulrich et al., 1991). SRT can be used to address negative effects of prolonged urban environment exposure by providing a basis for intervention in areas such as landscaping, interior design, and therapy (Honold, Lakes, Beyer, & Van Der Meer, 2016; Sahlin, Ahlborg Jr, Tenenbaum, & Grahn, 2015).

Learning objectives

By the end of this book chapter, you should be able to:

define and understand the underlying theories of SRT;
understand what evidence exists that supports SRT; and
identify specific intervention strategies for implementing SRT into real world situations.

What is Stress Recovery Theory (SRT)?

Roger S. Ulrich's (1991) investigated the psychological benefits of natural environments and his work subsequently generated much more research activity. Ulrich and colleagues devised a psycho-evolutionary theory in relation to natural environments: Stress recovery theory. Stress recovery, according to Ulrich, involves the recovery or restoration from excessively arousing states, both psychologically and physiologically (Ulrich et al., 1991). Stress recovery in this context is a part of the larger concept of restoration, which also encompasses factors such as recovery from under stimulation and recovery from anxiety (Ulrich, 1993).

Ulrich's theory proposes that, after being in a stressful space, a biological and almost automatic preparedness initiates a response (Ulrich et al., 1991). This, in turn, motivates the individual to leave that environment in order to produce a positive emotional change, regulate the physiological effects of the stressful space, and recharge the energy that was exerted during the stress response (Ulrich, 1993). Honold et al. (2016) re-emphasise this idea, stating that positive affect experienced by nature adjusts an individual's neurophysiological activation, which triggers nerve impulses that result in adaptive behaviours.

Perspectives of SRT

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Psycho-evolutionary perspective

As humans have evolved, nature has served an adaptive purpose (Van Den Berg, Hartig, & Staats, 2007). Aspects of the natural environment have been vital for human adaption and survival, for example plants as a food resource, for shelter and an indicator of water supply (Grinde & Patil, 2009). Ulrich et al. (1991) claimed that a common theme in literature on restorative environments is that humans appear to have an innate predisposition to direct more attention to and respond more positively to natural content. This reaction to nature appears to have been carried on from early human conditions, when elements of nature were vital for survival (Van Den Berg et al., 2007). Thus, this perspective proposes that positive evaluations for natural environments occur when the environment supports basic functions, such as shelter and food (Bringslimark, Hartig, & Patil, 2009).

This is supported by a concept known as the biophilia hypothesis, it implies that humans have an inherent inclination to interact with and be a part of nature (Grinde & Patil, 2009). Another way of looking at the evolutionary basis for human's nature reactions is by looking at the functional basis of recovery after fatigue. Ulrich (1993) explained that nature has enhanced survival by providing recovery from fatigue or other stressors. The ability to recover from fatigue and stress can preserve executive cognitive resources, such as complex problem solving and creativity, which have been vital in the evolutionary progress of humanity (Ulrich, 1993).

Attention perspectives

Another perspective that addresses the restorative utility of natural environments is based on attention. Kaplan (1995) devised the Attention Restoration Theory, which proposes that natural environments, as oppose to urban environments, can aid recovery from attention fatigue. According to the theory, natural environments that are full of interesting stimuli elicit involuntary attention, which requires little effort compared to directed attention (Berman, Jonides, & Kaplan, 2008). Thus, involuntary attention to natural stimuli gives directed attention capacity a chance to rests and replenish (Berman et al., 2008). When an individual then leaves this natural environment, they are able to better direct their attention to important tasks, since directed attention has had time to recover from fatigue (Kaplan, 1995).

Although this perspective has a larger emphasis on attention than Ulrich’s SRT, it still highlights the restorative qualities of nature on psychological functioning. Kweon, Ulrich, Walker, and Tassinary (2008) also highlighted that attention can be redirected from a negative experience to a pleasant stimulus, such as a nature setting. From this perspective, attention is redirected from negative emotions in order to sidetrack and focus on something else.

Ulrich’s theory emphasises the role of held attention, while Kaplan's (1995) theory highlights the role of involuntary attention in recovery from mental fatigue. Although Ulrich also suggested that nature does not actually possess qualities to recover from mental fatigue [explain?] (Ulrich et al., 1991), recent findings would suggest that both cognitive resources and affect could be influenced by nature (Raanaas, Evensen, Rich, Sjøstrøm, & Patil, 2011).

Affect and aesthetic preference

Ulrich (1983) explained two adaptive functions that exist in regards to emotion. These include an affective state immediately prior to an encounter with a visual stimulus, followed by a cognitive evaluation of a setting in terms of its significance to a persons[grammar?] functioning and well-being (Ulrich, 1983). The affective reaction of the environment motivates adaptive behaviour, and the extent to which cognitive evaluation will change emotion, will result in appropriate arousal change and subjective feelings towards the environment (Ulrich, 1983).

Ulrich (1983) identified several nature elements, which can influence aesthetic response (see Table 1). Contact with aesthetic stimuli can be regarded as a positive experience, since the perceived beauty of the stimuli produces pleasant feelings, thereby reducing tension (Grinde & Patil, 2009).

Table 1.

Visual properties influencing aesthetic preference and interest (Ulrich, 1983)

Visual property	Definition in terms of environmental properties	How aesthetic preference and interest is achieved
Complexity	Independently perceived components of a scene.	Moderate complexity
Structural properties	Visual configuration of a scene based on structure and patterns.	High structure
Depth	Some form of scale and/or distance for a scene (enclosedness).	High depth and environmental information
Ground surface texture	Visual texture in relation to a scene's ground (eg. evenly cut grass)	Even texture
Deflected vistas	Innate need to explore and gather information about landscapes; requires an element of mystery	Enough so that information can be gained at no risk (balancing curiosity and fear)
Water	Water promotes interest, positive feelings, and elicits an affective responce quickly	Preference for most scenes increase when water is present

In spite of the elements highlighted by Ulrich, Kaplan (2001) suggested that vegetation filled settings may still be preferred regardless of an environment’s specific qualities. This emphasises the importance of both an evolutionary and attention based perspective when investigating the restorative features of natural settings.

What does the evidence say?

Many studies have sought to extend on Ulrich et al's. (1991) original findings (Brown, Barton, & Gladwell, 2013; Ryan et al., 2010). These studies have focused on the positive impact that natural environments stimuli can have on affect, cognition, and well-being.

Ryan and colleagues (2010) produced data measuring vitality, defined as physical and mental energy. Results showed increased vitality when participants exercised outdoors, and decreased vitality when buildings were present during physical activity (Ryan et al., 2010). This study directly showed that vitality increased due to the presence of nature.

Additionally, Raanaas et al. (2011) examined how the addition of indoor plants to an office environment could affect executive functioning. Results showed increased attention capacity, when indoor plants were present. Raanaas and colleagues (2011) concluded that environmental factors could help restore central executive functioning. Studies like this support Kaplan’s (1995) theory that environmental factors can help restore attentional fatigue.

Various studies have also investigated SRT using physiological measures of stress. Brown et al. (2013) found that even a five-minute dose of nature exposure before a stressor occurred, altered heart rate, blood pressure, and respiration when recovering from stress. Additionally, Hartig, Evans, Jamner, Davis, and Gärling (2003) measured blood pressure in relation to restorative environments. Results revealed an increase in positive affect and a decrease in anger and aggression when walking in a natural environment (Hartig et al., 2003). The opposite effect was found when walking in an urban environment. This study even found changes in blood pressure, simply from sitting at a window during an attention task, highlighting again the power nature can have on stress and overall affect (Hartig et al., 2003).

Closer look: Stress recovery during exposure to natural and urban environments (Ulrich et al., 1991)

Ulrich and colleagues examined physiological measures of stress after exposure to a stressor in three different recovery environments. The results of the study revealed that participants in the natural environment recovery condition, experienced several physiological changes, including:

decreased fluctuations in skin conductance;
decreased blood pressure;
decelerated heart rate; and
decreased muscle tension.

For participants in the two urban environment recovery conditions, these measures stayed constant after exposure to the stressor, and in some cases, increased.

Research has also shown that not only visual nature, but also nature sounds can induce physiological changes (Annerstedt et al., 2013). Annerstedt and colleagues (2013) used a virtual simulation of nature scenery and sounds, and showed heart rate recovery from physiological stress for the sound and visual simulation condition, but not when only visual simulation was received. This suggests that the restorative benefits of natural environments may only be found in nature itself, as oppose to laboratory settings or even urban environments.

However, Ulrich (1983) suggested that higher aesthetic preference for an environment still exists when natural elements are added to urban environments. This has been shown by studies suggesting that nature environments in close proximity to urban areas may buffer the stress effects of the urban environment (Van Den Berg, Maas, Verheij, & Groenewegen, 2010; Wells & Evans, 2003). Kweon and colleagues (2008) supported this view that any form of nature has the potential to reduce stress. By measuring task related frustration, Kweon et al. (2008) found that the proportion of nature paintings in a room decreased state anger produced by the task, by reducing stress.

Window views of nature have also been found to produce positive effects. Kaplan (2001) found that people who lived in homes with views of nature rated higher satisfaction with their neighbourhood and better effective functioning (Kaplan, 2001). Another study found that sun penetration through office spaces had a significant effect on job satisfaction and general well-being (Leather, Pyrgas, Beale, & Lawrence, 1998). In regards to stress, Honold et al. (2016) produced findings that showed lower cortisol levels in residents whose homes were surrounded by a large range of vegetation, compared to those whose homes did not.

How can SRT be applied?

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Landscaping

Landscape design is one area in which the evidence of SRT can be implemented. Chang and Chen (2005) suggested that having larger trees surrounding office buildings might benefit office workers on higher building floors. This approach takes an inside-out view of horticulture landscaping, as oppose to the usual outside-in views, which only focus on how an area looks on from the outside. By having nature visible from high stories, work related stress may be reduced (Chang & Chen, 2005). However, due to the complexities of an intervention such as this, indoor plants and window flower boxes were also suggested as a good intervention method (Chang & Chen, 2005). The use of indoor plants in the work place has been suggested by numerous studies (Largo-Wight, 2011; Raanaas et al., 2011).

Workplace environments

Aries, Veitch, and Newsham (2010) showed that employee discomfort reduced when a window view was visible in the workplace, and these conditions were rated as more attractive to look at (Aries et al., 2010). The finding that links to Ulrich’s (1984) original view of aesthetic pleasure being partly responsible for the affective changes that occur in the presence of nature.

Additionally, it may be beneficial for landscape designers to take into account which side a structure will face. Previous evidence has shown that sun penetration can significantly influence well-being and satisfaction of workers, so an implication may be for designers to make sure that every window in a building will receive sunlight at one point in the day at least (Leather et al., 1998). Lottrup, Grahn, and Stigsdotter (2013) also emphasised the importance of green outdoor views in workplaces for reducing stress.

Town planning

In regards to town planning, various pieces of evidence stress the importance of green space access in urban environments (Honold et al., 2016; Lottrup et al., 2013). Wells and Evans (2003) found that the impact that life stressors had on the children in the sample varied depending on the level of nature exposure they received. As natural environments promote social support and attention restoration for children, it was suggested that nature exposure could play an important role in a healthy child’s development (Wells & Evans, 2003). A finding such as this suggests that designing the school location in a town plan, may play an important role in a child’s development (Berman et al., 2008).

Linking back to Ulrich’s original idea about aesthetic preference and affective state is a study from Van Den Burg et al. (2003). The researchers stressed the importance of public preference when managing or planning elements of a location, and that a lack of natural elements may risk depriving humanity of a simple restorative resource (Van Den Burg et al., 2003). Hansmann, Hug, and Seeland (2007) also emphasised the importance of attractive green space design in public areas, due to the link between preference and restoration. For town officials, the benefits of catering to the public’s preferences may outweigh the cost of improving environments, according to Sheets and Manzer (1991). By maintaining a public green space, residents may view their city services as better, improving the public's image of the place itself (Sheets & Manzer, 1991).

Tips for everyday stress recovery

Adding indoor plants to a room or office space.
After completion of a stress-provoking task, such as presenting in front of an audience at work, spend some time outdoors afterwards, surrounded by different elements of nature.
Take a walk outside after completion of an exam.
Take lunch breaks outdoors, and maybe find a tree or river to sit by.
Add pieces of nature art to office or room walls.

Nature-based therapy

Despite the lack of evidence supporting nature’s effect on physical rehabilitation, new research has focused on how nature can be used in therapeutic intervention of mental illness. Nature-based therapy programs entail an intervention method that aims to aid treatment of ill health combining natural methods of therapy with access or activity within natural environments (Annerstedt & Währborg, 2011). A systematic review conducted by Annerstedt and Währborg (2011) found positive results for nature-based therapy in psychological, social, physical and intellectual factors. However, follow up effects were not as clear, and specifically wilderness therapy showed high recidivism. Research that has looked at the long term effects of nature-based therapy found decreases in self-reported burn out and depressive symptoms, as well as increased well-being that continued throughout follow up assessments (Sahlin et al., 2015).

Barton, Griffin, and Pretty (2012) suggested that combining exercise elements, nature, and even social contact could improve mood levels and self esteem in a clinical sample with mental illness. This has been supported by a number of studies highlighting that combining exercise and nature contact can increase the restorative qualities of natural environments (Barton & Pretty, 2010; Ryan et al., 2010).

Other studies have also found promising evidence for therapeutic effects of nature on mental illness. Weslund (2015) found evidence that veterans suffering from post-traumatic stress found that contact with nature provided additional support[improve clarity]. Raanaas, Patil, and Hartig (2012) also found that an unobstructed bedroom view to nature correlated with self-reported increases in physical and mental health in a sample of residents in a psychiatric rehabilitation program. This research suggests that, although research is limited and requires further investigation, the use of nature for therapeutic purposes looks promising, and should be researched further.

Quiz

Take the following quiz to test your knowledge:

Conclusion

SRT has sprouted much research into the restorative effects of contact with nature (Ulrich et al., 1991). In a society that focuses a lot on events that occur in urban environments, such as work and education, it is of no surprise that being surrounded by elements of nature could help elevate stresses from everyday life. Research in the past few decades has looked at physiological changes that occur in the presence of nature, and it does appear that contact with nature provides a stress restoration quality. SRT has many implications in the planning and landscaping of institutions, residences and even whole towns. Additionally, SRT research has suggested that nature may also be useful for therapeutic interventions. Nature-based therapy looks to be an encouraging area for future research, extending Ulrich’s original theory into an application that could improve the well-being of those who are mentally ill, as well as those looking to wind down from stresses of everyday urban life.

References

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External links

Stress recovery during exposure to natural and urban environments

Nature-assisted therapy: Systematic review of controlled and observational studies

	Biophilia hypothesis
	Environmental psychology
	Theory of biophilia
	Attention restoration theory

	Physical injury
	Attentional fatigue
	Stress
	Anxiety

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