# Psychology of natural scenes
## Overview

This is an open working space for theory and research about the psychological and physiological processes and effects of exposure to natural environment scenes. Feel free to contribute.

## Goals

Goals this resource is working towards include:
* Review and test theory about the possible influence of viewing, being in, and interacting with, different types of natural environments on outcomes such as:
** psychological stress/relaxation
** emotion/mood
** cognitive performance and fatigue
** physical health
* Identification and collation of freely available nature-based images for current and future research studies
* Development of a means of electronically presenting images and recording participant responses
* Development of restorative environments
Creating and experiencing natured-based restorative environments has many implications for human well-being, particularly given increasing urbanisation and dwindling access to natural environments.
Some possible research questions include:
* What are the physical and psychological effects of exposure to natural environments and stimuli?
* How and why is nature beneficial?
* Are natural environments necessarily more beneficial than urban environments? A well-designed urban environment can be very restorative. So, what are the key elements/requirements of psychologically restorative environments?
* Are some aspects of environments more important for facilitating particular outcomes (e.g., water -> calmness?).
* What is the effect of natural stimuli perceived through different senses (i.e., sight, sound, touch, taste, smell)?
* Single scene vs. multiple scenes vs. video - What are the differential psychophysiological effects of looking for a period of time at a single scene vs. multiple scenes or video of scenes?
* Bowler et al.'s (2010) review indicated a need for more rigorous and objective evaluation of interventions which aim to use the natural environment for health promotion. The review recommended that research compare effects for different populations, environments, and social contexts, and consider the longer-term significance of repeated exposure on health.

## Theories

Most theories which seek to explain the human health benefits of exposure to natural environments draw broadly on evolutionary theory and, subsequently, the biophilia hypothesis.
More specifically, however, the two most commonly utilised theories are:
* Stress recovery theory (SRT) focuses on how natural environments can reduce physiological stress and aversive emotion. Note that this is sometimes also referred to as stress reduction theory.
* Attention restoration theory (ART) focuses on how natural environments can engage involuntary attention, and thus allow recovery of a fatigued directed attention system.
These theories are summarised in more detail in the following sections.

### Biophilia hypothesis

* The Biophilia hypothesis derives from evolutionary theory.
* It argues that humans have an affinity for nature-like patterns and stimuli and life-like processes because we were primarily exposed to nature during our evolution. It is only relatively recently that we have lived in such artificial, urban environments and, in that time, there's been little genetic adaptation.
* The key citation is Wilson (1984)
* See also biophilia hypothesis (Wikipedia)

### Attention restoration theory

* Kaplan and Kaplan's (1989) attention restoration theory (ART) seeks to explains the positive, restorative effects of green spaces on mental fatigue (overuse of directed attention). According to the ART an environment has restorative potential (qualities) if four components are available in the human-environment interaction:
** Being away
** Fascination (effortless attention)
** Coherence (coherent physical environment of sufficient scope; sense of order, structure, and harmony)
** Compatibility (match between psychological needs and environment)
* According to ART, restorative environments contribute to restoration by recovering directed attention capacity and by clarifying and restructuring thoughts (de Vries, ClaBen, Eigenheer-Hug, Korpela, Maas, Mitchell, & Schantz, 2014, p. 227)
* The theory of two types of attention (involuntary and voluntary) goes back to the work of James (1892). Voluntary (or directed) attention requires effort, and involuntary attention (or fascination) requires no effort (cited in Kaplan, 1995). See Attention restoration theory (Wikipedia).
* Measures of the four theoretical elements of restorative environments proposed by Kaplan have been operationalised, including:
** The Perceived Restorativeness Scale - there are long, short, and very short versions.
** The Felsten (2009) measures of perceived restorativeness (based on Berto (2005) and Herzog et al. (2003)) used one item for each of the four components, modified from the single-item scales of Berto (2005) measured with a 7-point Likert scale from "1 = Not at all” to “7 = Very Much":
*** Being away: “Some settings allow you to feel like you are far away from everyday thoughts and concerns. How much does this setting allow you to get away from it all, relax, and think about what interests you?”
*** Extent: “Some settings, large or small, can feel like a whole world of their own, where you can get completely involved in the setting and not think about anything else. How much does this setting feel like a world of its own?”
*** Fascination: “How much does this setting draw your attention without effort and easily engage your interest?”
*** Compatibility: “How much does this settings make you feel comfortable and at ease?”
*** Overall perceived restorativeness: "Overall, how much do you agree that this setting would be excellent for taking a break and restoring your ability to study for an exam or work effectively on a demanding project?" This question was similar to the single-item measure of perceived restorative potential used by Herzog et al. (2003) that asked students to recall a time when sustained effort led to fatigue and then rate how good various settings would be to take a break and restore ability to work effectively on a project.
* A systematic review of ART is being conducted: http://www.ecehh.org/research-projects/attention-restoration-theory-a-systematic-review/
Kaplan (1984) Kaplan, R. (1984). Impact of urban nature: A theoretical analysis. Urban Ecology, 8, 189-197.
Kaplan, 1995
* William James didn't address the potential that directed attention could be susceptible to fatigue.
* Directed attention requires effort, is under often under voluntary control, inhibits attention to distraction, helps to achieve focus.
* Sustained mental effort leads to fatigue of directed attention
** This can be explained in terms of evolution: In the past, being alert to one's surroundings was probably more important than being focused on one thing for a particularly long period of time. Also in times of the less-evolved human, things like caves, blood, danger and wild animals which were essential to survival were innately interesting. Today these things remain innately interesting, but they are less essential to survival. Instead, more tedious tasks are more important to every day life, thus one must resist being distracted by that which is more innately interesting.
* For early humans, what was "interesting" and what was "important" were synonymous. These days, it's not the case, where people have to pay attention to uninteresting, repetitive work (such as work in a factory).
* Directed attention is particularly important in:
** problem solving, where habitual, learned responses are not appropriate
** inhibiting instinctual 'flee' response, because often these days, fleeing is not appropriate/beneficial (e.g. in a stressful job interview.
** perceiving and understanding things which are not inherently interesting
** certain important jobs like air traffic control, where one must focus on that which is not intrinsically interesting and there are many inherently interesting things around.
** Inhibiting responses allows us time to think about our best possible response. It also allows us to act reasonably and responsibly in social situations by following norms rather than the following impulse
** In the modern world, jobs have now become more and more specialized and sophisticated. Decreased variability possibly makes a jobless inherently interesting, thus using more directed attention.
** Thus, directed attention is key to being successful in modern life solutions
The restorative process (Kaplan, 1995)
* Because directed attention is susceptible to fatigue, it needs time to rest so it can again work effectively.
* Sleep is one way to gain this rest; but sleep is often not appropriate in given situations, so an alternative is needed
* Involuntary attention, requiring no effort, allows directed attention to rest. It is essential for, but in itself not sufficient to the rest and recovery of directed attention.
** being in a novel area where one is surrounded by things which capture involuntary attention (which Kaplan calls "fascination") is beneficial, but so is changing the direction of one's gaze, or seeing an old environment in a novel way.
** a restorative environment involves a sumptuous and coherent set of experiences that are perceived as another "world", rather than a series of unrelated perceptions.
** natural settings like forests, streams, the ocean, and mountains meet these conditions.
** nature provides people with sources of 'soft' (i.e. undramatic) fascination, such as the swaying of trees in the wind, sunsets, or footprints on the beach.
** People are also attracted to environments because of the certain activities that can be performed in that environment i.e. fishing in a lake, hunting in a forest, planting in a garden bed.
Kaplan (1995) on stress
* Stress is a reaction to a potentially negative situation. Stress is triggered by a sense of physical or psychological harm (either impeding or current) or by a sense of possessing inadequate resources. Due to the diversity of situations that prompt stress reactions, it is possible that it is actually depletion of some underlying resource which causes stress and tension.
* The requirements of some underlying resource is that it
** plays a pivotal role in a person's effective functioning
** is vulnerable to depletion
* directed attention fits these requirements because it effects functioning through inhibition and important attention to uninteresting but essential tasks. Hancock and Warms (1989) (cited in Kaplan) suggest that lack of attentional resources can lead to stress.
Kaplan (1989) on stress
* Stress and mental fatigue are distinct constructs, where stress is a preparatory response, and mental fatigue is an outcome.
Kaplan 1989 on restoration
* People describe 'escape' as a way to find relief from directed attention. Escape means an absence of that which is causing the fatigue and implied
** "get away" from what is causing fatigue (i.e. physically remove yourself)
** "put it aside" (i.e. move it)
** mentally focusing on something else. Under these conditions, however, one might end up in a closed, empty room; so there must be more to "restorativeness" than simply "escape" (p. 183)
Key terms by William James, 1982 (from Kaplan & Kaplan, 1989)
* Voluntary and attention
* Involuntary attention (that which is exciting)
* Inhibition
* Kaplan & Kaplan deducted that fatigue comes from resisting exciting stimuli whilst trying to concentrate on less exciting things (i.e., using voluntary or "directed" attention)

### Stress recovery theory

* "Compared to the ART, which is focused on cognitive processes, Ulrich (1983), Ulrich et al.'s (1991) stress reduction theory (SRT) is more focused on emotional and physiological processes. The SRT is based on the belief that viewing or visiting natural environments after a stress situation rapidly promotes physiological recovery and relaxation (Ulrich, 1983)." (de Vries et al., 2014, p. 227)
* Ulrich et al. (1991)
* Stress reduction theory (Motivation and emotion book chapter, 2020)

### Processing fluency theory

* Processing fluency theory of aesthetic pleasure (Wikipedia)
* Phytophilic Response Module (PRM) (Joye & ven den Berg, 2011)

### Conditioned restoration theory

Conditioned Restoration Theory suggests that nature is restorative because modern humans have mostly leisurely, positive experiences with nature. These positive feelings are conditioned with nature, and subsequently retrieved when presented with associated stimuli such as trees, pictures of landscapes, and birds singing.

## Reviews of effects
### Frumkin (2001)

A useful review of the research literature about the effects of nature on human health was provided by Frumkin (2001).

### Bowler et al. (2010) meta-analysis

* Bowler, Buyung-Ali, Knight and Pullin (2010) conducted a systematic review of 25 studies about the benefits to human health from exposure to natural environments (including public parks, green university campuses, and synthetic environments, such as indoor and outdoor built environments).
* The most common outcome measures were self-reported emotions.
* Based on a meta-analysis, "there was some evidence of a positive benefit of a walk or run in a natural environment in comparison to a synthetic environment. There was also some support for greater attention after exposure to a natural environment but not after adjusting effect sizes for pretest differences. A meta-analysis of data on blood pressure and cortisol concentrations found less evidence of a consistent difference between environments across studies." (p. 1)
* Most studies investigated the effects of active participation in natural environments, particularly walking or running, but also including wilderness backpacking, gardening, passive/sedentary activity or a mixture of activities (p. 4).
* None of the studies investigated more than one type of natural environment.
* Bowler et al. (2010) concluded that "the studies are suggestive that natural environments may have direct and positive impacts on well-being, but support the need for investment in further research on this question to understand the general significance for public health" (p. 1).
Table 1.
Pooled Effect Sizes (Hedges' g) and 95% CIs Comparing Before and After Activity in the Natural Environment (adapted from Bowler et al., 2010).
| Outcome | Effect size | 95% CI | No. studies |
| Attention | 0.23 | (-0.30, 0.76) | 3 |
| Energy | 0.76 | (0.30, 1.22) | 5 |
| Anxiety | 0.52 | (0.25, 0.79) | 6 |
| Tranquillity | 0.07 | (-0.42, 0.55) | 7 |
| Anger | 0.35 | (0.07, 0.64) | 6 |
| Fatigue | 0.76 | (0.41, 1.11) | 4 |
| Sadness | 0.66 | (0.16, 1.16) | 3 |
| Systolic BP | 0.02 | (-0.42, 0.38) | 4 |
| Diastolic BP | 0.32 | (-0.18, 0.82) | 3 |
| Cortisol | 0.57 | (-0.43, 1.57) | 4 |
Note. The sign of the effect size reflects the benefit on health (positive effects indicate greater attention, energy and tranquility but lower values for the other outcomes). Number of studies reflects the number of studies for which there was data available to calculate this effect size (i.e., with pre- and post-test data).

### McMahan and Estes (2015) meta-analysis

McMahan and Estes (2015) conducted a meta-analysis of 32 studies which examined the influence of exposure to nature on positive and negative affect. Overall, there were moderate enhancements of positive affect and small reductions in negative affect for participants exposed to natural environments. Effects were larger for those exposed to real natural environments as opposed to, say, pictures of natural environments.
McMahan and Estes (2015) explain that "emotional responses to natural environments, like all emotional responses, are likely functional in nature, with the specific emotions elicited in response to exposure to a natural environment depending on the degree to which that environment signals the presence of evolutionarily significant resources or hazards." (p. 515).

### Capaldi et al. (2015) traditional review

Capaldi, Passmore, Nisbet, Zelinski, and Dopko (2015) reviewed theory and research about the potential for engagement with nature to improve wellbeing.

### Pearson and Craig (2014)

A brief review of the mental health benefits of natural environments is provided by Pearson and Craig (2014). They suggest that there is a need for research that aims to establish:
* which properties of environments make them more or less “restorative”
* the relationship between perceived restorative properties of an environment and objective measures of improved cognitive function
* the optimal form of interaction with restorative environments that is most likely to lead to mental health and well-being benefits.

### McMahan and Estes (2015) meta-analysis

McMahan and Estes (2015) examined evidence about the effect of contact with natural environments on positive and negative affect. Notable findings included that:
* 32 studies; 2356 participants
* There was a moderate increase in positive affect and a smaller decrease in negative affect compared to control conditions
* The effects on positive affect were greater than on negative affect
* There was considerable heterogeneity in the effect of nature on positive affect
* Type of emotion assessment (PANAS effects were strongest), type of exposure to nature (real contact produced larger effects than simulated contact), location of study (wild nature had a stronger effect than cultivated nature, but not by much), and mean age of sample were found to moderate this effect (older participants experienced a stronger effect, but there was considerable age restriction in the sample).

### McMahan (2018) review

McMahan (2018) reviewed theory and research about the effects of exposure to nature on subjective well-being. He concluded that there is robust support for the positive effects of nature on subjective well-being. However, he suggested that there is a need for additional research that examines:
* Group differences in responses to nature (based on demographic variables e.g. age, income level, ethnicity)
* Causal mechanisms explaining the relationship between nature and well-being (e.g. awe, meaning in life, positive social experiences)
* Environmental factors influencing the effects of nature on well-being (e.g. familiarity, pleasantness, type of environment)

## Key researchers and studies

This section summarises key researchers and key studies.

### Kaplan

The Kaplans (along with Ulrich) have been two of the main early researchers of the effects of exposure to natural views.

#### Kaplan & Kaplan 1989

* One way people categories a scene is by how much human influence is seen in the image (p. 28), or of perceptions of 'natural' versus 'built' (p.30)
* Human influence is a prominent dimension by which people categories images (p.31) and is perceived by cues such rubbish, abandoned cars houses and bridges (p.29). Human influence does not necessarily mean buildings or additions to a scene, it can be seen through things like clear-cutting (p.44)
* Peoples 'preferences' can very unique, and this can be seen in their choices of posters and images which they surround themselves with (posters, photos, desktop images, screen savers), but Kaplan & Kaplan suggest (p. 41) that there is also a universal preference, and they aim to elucidate these.
* Across the animal kingdom, suitable and safe habitats are preferred, and this is potentially a characteristic of humans, too (p. 41)
* Majority of studies find that images which show the most obvious signs of human influence are least preferred.
* images can also be clasified in terms of 'affordance' i.e. what the environment has to offer the viewer; what he/she is able to do in this environment (p.32)
* one category of affordance is 'openness', another is spatial definition' (p.32)
* openness is where the sky is a dominant feature in the image, and where the image lacks any other distinct figures (p.32)
* Anderson (1978, cited in Kaplan & Kaplan '89, find article!): Included in the openness category are open and unused landscapes such as meadows, uncultivated fields, wildlife openings
* Spatial definition means having a few natural land marks (e.g. trees) to allow preception of the spacial (eg size & depth) aspects of the scene (p.34). Scenes with high spacial definition are open areas with few landmarks (p.35). Scenes with low spacial definition are very open areas with very little or no landmarks (easier to become lost in), or are the opposite; densely populated, seemingly impenetrable areas (p.35) which would be hard to see/move around in (p.37). Dense ((Woodcock 1982 in Kaplan p47) and 'blocked' (Gallagher 1977 cited in Kaplan p.47) were natural scenes that were less preferred.
* Not all scenes showing human influence were rated poorly, 'small structures in natural settings' were much preferred, which included 'boardwalk' scenes, where a wooden boardwalk was present in an otherwise entirely natural scene (Miller, 1984 cited in Kaplan). Scenes containing a boat have also been found to be moderately preferred (Hudspeth, 1982, cited in Kaplan)
* Water scenes are often the most preferred (p. 50). Industrial scenes are often least preferred (p50)
* Cultural differences exist (p. 51). Quote from Kaplan (p.51) "Americans looking at Australian landscapes are not likely to understand that trees without leaves are diseased rather than showing seasonal variation because they are not aware that Australia has no native deciduous trees (Kaplan & Herbert, 1987)"
* The need to explore is an inherent human attribute (p. 51), as such humans will prefer environments in which they can explore (p. 52). Humans experience negative affect, like frustration and aggravation, when experiencing environments which they struggle to comprehend, so easy to understand environments are preferred (p. 51)
* Higher coherence and complexity of the scene predict higher preference. Coherence refers to the organization of sizes, textures, and brightness (p. 54). Complexity refers to a scene having a number of different elements (p. 53). A scene that is high on complexity and low on coherence will look messy. One which is high on coherence and low on complexity will be simple, clear, and underwhelming. A scene that is high on both (i.e. one which is high on 'legibility') will be rich and organized (see Table 2.2 p. 54). Complexity (e.g. landmarks) help the memorability of a scene, which increases preference, as a memorable scene will be easier to function/move around in.

### Ulrich

Ulrich (along with the Kaplans) have been the key early researchers of the effects of exposure to natural views.
* Ulrich (1979). 18 minute slide show of urban and nature scenes (N = 46). Nature scenes enhanced positive affect and reduced fear, whereas urban scenes increased sadness. There also some evidence that nature scenes tended to alleviate Aggression/Anger whereas urban scenes tended to exacerbate such feelings.
* Ulrich (1981). Natural versus urban scenes: Some psychophysiological effects. (N = 18).
* Ulrich (1983). Aesthetic and affective response to the natural environment.
* Ulrich (1984). View through a window may influence recovery from surgery. A classic study of hospital patients and windows with natural settings versus brick walls.
* Ulrich (1986). Human responses to vegetation and landscapes.
* Ulrich, Simons, Losito, Fiorito, Miles, and Zelson (1991). Stress recovery during exposure to natural and urban environments.
* Ulrich (1993).

### Hartig

* In a series of experiments comparing cognitive functioning in a group exposed to natural environments versus those exposed to urban environments, Hartig ((1991) cited in Kaplan 1995, find article) found that after exposure to environments, those in the natural group had a higher level of cognitive functioning (as measured by proofreading tasks), compared to those in urban environments. Performance on cognitive tasks is closely linked to directed attention because success on such tasks often involves concentration on tedious tasks. This suggests that exposure natural settings give directed attention time to rest and be more effective when it was needed to complete cognitive tasks.
* Hartig, Mang, and Evans (1991) examined the effect of wilderness vacations, nonwilderness vacations on attentional fatigue (proofreading was superior for those who went on wilderness vacations).

### Kahn

* Peter Kahn Jr.
* Friedman, B., Freier, N. G., Kahn, P. H. Jnr. (2008). Office window of the future? Field-based analyses of a new use of a large display. International Journal of Human-Computer Studies, 66(6), 452-465, DOI: 10.1016/j.ijhcs.2007.12.005.

### Herzog

Herzog 1989
* Aimed to investigate the Kaplans' "informational' approach", which relates to "content" and "process".
* Images can be interpreted in terms of their general and specific contents, where the general content refers to what one assumes they can do in the environment, and specific contents refer to the physical aspects within the image, such as trees, water, etc.
* Processes refer to 'understanding' and 'exploration', which include depending on amounts of nature, typicality, mystery, legibility, complexity, coherence, refuge, age and spaciousness all contribute to the preference for natural and urban scenes.
** Spaciousness: How much room there is to wander in a scene, how far away is the farthest point
** Refuge: to be hidden, the chance to see without being seen
** Coherence: how well structured is the scene
** Complexity: how many elements are in the scene
** Mystery: finding out more if you were to walk deeper into the scene
** Typicality: How representative is the image of the category which it belongs to
** Nature: how much 'foliage' is there in the scene
** Age: how old do the elements in the image seem to be
* A sense of familiarity to a place would aid understanding, but too much familiarity would detract from 'mystery'. In this study, 'familiarity' was instead referred to as 'typicality', describing whether or not the image was a good or typical example of the category from which it is a part of. Purcell, Lamb, Peron and Berto (2001) found that familiarity had a curvilinear relationship with restorativeness and preference, where the most familiar scenes were those which were moderately preferred and perceived as moderately restorative.
* The above 'processes' were used as predictor variables, and the criterion variable was 'preference' defined as 'how much you like the scene, for whatever reason'
* Pictures were further classified into one of four groups:
** Older buildings
** Concealed foreground, where the foreground was mostly (but not entirely) concealed
** Tended nature, where images exhibited cultivated, well looked after natural elements (such as trimmed hedges)
** Contemporary buildings
* Tended nature was the highest in preference, and older buildings were the lowest.
* As for processes, the only significant predictors were nature, coherence, and mystery. Adding image categories as predictors (i.e. 'tended nature') accounts for no extra variance in preference scores.
* Age as a process did not account for any variance in preference scores, which was interesting considering that older buildings were the least preferred category. This is possible because the older buildings may have been forgotten for some time hence contained messy, disorganized grounds that needed tending to.
* These findings support the informational model where coherence is an 'understanding' variable and mystery is an 'exploration' variable.
* 'Typicality' was uncorrelated with preference and only had moderate correlations with the other predictors. Participants were possibly overwhelmed by having to make this assessment regarding so many images, so a reversion back to the original term of 'familiarity' is recommended.
* The other five insignificant predictors look to form part of a cluster which may be explained by 'coherence'

#### Herzog et al. 2003

* "Assessing the restorative components of environments" operationalized and tested the four components of ART as predictors of the restorative benefit of natural and urban scenes
* ~500 UG psychology participants rated 70 scenes on 1 of 10 variables of interest
* The major criterion variable was Perceived Restorative Potential (PRP), defined as: "Recall one of those times when you worked hard on a project that required intense and prolonged effort. Remember how it felt. You probably reached a point where you could tell that your ability to work effectively had started to decline and that you needed a break. You needed to do something during the break that would restore your ability to work effectively on the project. Put yourself in that mindset now and then please rate each of the settings you will be shown on how good a place you think it would be to take a break and restore your ability to work effectively on the project." (p. 162)
* The primary set of predictor variables consisted of the four components of a restorative setting as specified by ART:
** Being Away: “Sometimes even when you are very near home it can feel like you are far away from everyday thoughts and concerns. How much does the setting have that feeling of being away?”
** Extent: “Sometimes even a small setting can feel like a whole world of its own. It can seem like there is enough room to get completely involved in the setting and not even think about anything else. How much does the setting seem like such a ‘whole other world’?”
** Fascination: “How much does the setting draw your attention without any effort on your part? How much does it easily and effortlessly engage your interest?”
** Compatibility: “Settings can either help you feel comfortable and at ease or they can make it hard to do so. How much does it seem like the setting would make it easy for you to feel comfortable and at ease?”
** All ratings used a five-point rating scale ranging from “very high (highest possible rating)” to “not at all (lowest possible rating)”.
* Felsten (2009) used adaptations of the Herzog et al. 2003 measures.

### Pretty
#### Pretty et al. (2005)

* Discusses three types of involvement with nature: viewing, presence, and participation. Each type of involvement appears to facilitate a variety of health and well-being benefits.
** Viewing nature, as through a window, or in a painting
** Being in the presence of nearby nature, which may be incidental to some other activity, such as walking or cycling to work, reading on a garden seat or talking to friends in a park
** Active participation and involvement with nature, such as gardening or farming, trekking or camping, cross-country running or horse-riding
* found that viewing pleasant urban or rural photographs after exercise led to a greater improvement in self-esteem compared to viewing no photos or unpleasant ones; where 80% of participants experience increased self-esteem after viewing pleasant rural images vs 65% of those in the urban pleasant category (which was the same as the no-image control). Other findings included:
** Viewing unpleasant scenes led to a decrease in self-esteem when the positive effects of exercise were accounted for.
** Viewing pleasant rural scenes provided an increase in all 6 mood measures, though the increase was not always significant.
** Viewing pleasant urban scenes had a similar effect, but 5 out of 6 results were significant
** Significant reductions in depression-dejection (as measured by the POMS) for urban pleasant scenes, no others.
** More reduction in tension-anxiety for pleasant scenes than for unpleasant ones.
Barton and Pretty (2010) conducted a meta-analysis of green exercise studies.

### Korpela

* In 2002 used affective priming effect to test affective associations with natural and urban environments.
* Affective priming effect: Shorter reaction times to target when 'prime-target' pairs are congruent (p637)
* Participants were presented with a series of image-voice combinations which consisted of natural and urban images, and voices conveying either positive or negative affect. After the presentation of the stimuli, participants were asked to identify if the voice was joyful, angry or neutral. The total stimulus lasted for either .45 of a second or 1.45 seconds.
* Results show and interaction between image and tone-of-voice, where participants responded quicker to urban-negative and natural-positive pairs compared to urban-positive and natural-negative pairs.
* This suggests that natural and urban environments produce automatic and rapid effectual responses
Green spaces in natural settings (beach, lake, ocean, park, and forest) predominate among favorite places and are underrepresented among unpleasant places (Korpela, Hartig, Kaiser, & Fuhrer, 2001). Respondents in this study noted that their favorite places elicited feelings of relaxation, happiness, and excitement.
Korpela, K., Kyttä, M. & Hartig, T. (2002). Restorative experience, self-regulation and children’s place preferences. Journal of Environmental Psychology, 22, 387-398. doi:10.1006/jevp.2002.0277
Korpela, K., Hartig, T., Kaiser, F. & Fuhrer, U. (2001). Restorative experience and self-regulation in favorite places. Environment & Behavior, 33, 572-589. doi: 10.1177/00139160121973133
For more articles by this author, see: http://www.favoriteplace.info/Korpela_Kalevi.htm

### Berto
#### Berto (2005)

* This study cognitively fatigued participants, then exposed them to restorative environments, nonrestorative environments or geometrical patterns, and then re-tested cognitive performance.
* Only participants exposed to the restorative environments improved their performance on the final attention test. This
improvement occurred for participants viewing the scenes in the standardized time condition and in the self-paced time condition.
* The results were consistent with the Attention Restoration Theory.

## IVs and DVs

There are many possible independent variables (IVs) that potentially could be manipulated or controlled. These broadly relate to the type of environment and type of activity.
Dependent variables (DVs) include physiological (such as heart rate, blood pressure, hormones) and psychological indicators of health (such as mood, stress, and cognitive capacity).

### IVs

Possible independent variables - aspects of environments - that may influence their effects on human well-being.

#### Natural vs Urban

* Green, natural space
** 'Green' includes parkland, forests, fields (White et al.)
** Natural environments include forests, canyons, desert landscapes, mountain ranges (Tinio & Leder, 2009)
* Green scenes are preferred over brown ones (Pretty et al. 2005). But would this translate to populations who live in browner (drier) natural landscapes?
* Synthetic, artificial, built, urban, human-made space
** 'Built' includes roads, walls, buildings, constructions (White et al., 2010)
** "human-made" scenes include city skylines, bridges, road systems, houses (Purcell et al., 2001).
* From most preferred and most highly rated on a Perceived Restorativeness Scale(Purcell et al., 2001):
** Lakes
** Hills
** City streets
** Houses
** Industrial zone

## Real vs picture vs digital
#### Water

* People tend to prefer environments which contain water:
** Water is one of the most important aesthetic landscape elements (Kaplan & Kaplan, 1989).
** Many cities and towns have been built along coastlines and other bodies of water such as rivers and lakes (White et al., 2010).
** Water seems to enhance the pleasantness of a scene (Pretty et al., 2005; White et al., 2010). For example, college students preferred campus environments that featured nature and water (Felsten, 2009). Thus, water can be a way to manipulate the "pleasantness" of urban environments (White et al., 2010).
* People who live near coastal environments appear to be healthier, with particular benefit to people in lower socio-economic circumstances (Wheeler, White, Stahl-Timmins & Depledge, 2012).
* However, other studies have found that viewing water has no additional cognitive restoration effect above and beyond that of viewing natural environments without water (Neilson et al. (2016, 2017).
* The first study to measure the psychological effects of exposure to water-containing environments was by Ulrich (1981; N = 18).)
* Some studies remove the potential effect of water by treating it as a confound. These studies intentionally selecting images which do not contain water, in order to focus on other variables.[factual?]
* Water may have a "dose effect" (i.e., more water means higher restorative properties) (White et al., 2010). White et al. (2010) found that the most preferred views contained two-thirds water; those with less than one-third of water or scenes containing only water were rated less positively (which shows the importance of diversity, edges and borderlines as well as the need for a context of water together with surrounding land) (Völker & Kistemann, 2011). However, the subsequent studies by Neilson et al. (2016, 2017) have not replicated a dosage effect.
* For a review, see Völker and Kistemann (2011)

#### Pleasant vs Unpleasant

* The 'pleasantness' and 'preference' of a scene have found to be dependent on mystery, coherence and nature (Herzog, 1989)

#### People

* The presence of people (Herzog, Kaplan and Kaplan 1976, cited in Herzog 1989), animals in images affect their pleasantness. This can either be balanced by creating subcategories which include people, animals, objects or none of these. This would drastically increase the amount of categories (from 4 to 16), greatly increasing the length of time taken to complete our measures and placing undue inconvenience on participants (and due to our moderate-sized sample, a between-groups design with 16 conditions could be detrimental to the power (is this the right word?) of this design). Instead, the confounding effect of people and animals will be controlled by excluding them from our images.

#### Weather

* Weather can influence the pleasantness of a scene (White et al., 2010), and should, therefore, be controlled for (i.e. all scenes should have similar weather conditions). People have been shown to dislike dark skies and thundery clouds (Pretty et al. 2005)

#### Colour

* In a study of 14 participants before and after five minutes of exercise bike cycling whilst watching a video of rural cycling scenery (full colour (unedited), red, or gray) there was:
** Lower total mood disturbance and ratings of perceived exertion during the Green condition compared to Red and Gray.
** Anger was higher after the Red condition.
** Tension, depression, fatigue, vigor, and confusion did not differ among conditions.

#### Structures

* Trees contribute to pleasantness, as do sky-scrapers and city-scapes (Pretty et al. 2005).

#### Unpleasantness

* Contributors to unpleasantness include: broken windows, rubbish, scaffolding, graffiti, other damage or degradation, abandonment or desertion (Pretty et al.)

#### Image quality

* Tinio and Leder (2009) assessed differences in likability of natural versus human-made and high image quality (i.e. high resolution, vibrantly coloured, well-contrasting, sharp images). They found that natural images were liked more than human-made ones, and that high quality images were liked more than low quality ones. natural-high quality M = 5.47, human-made high quality M = 4.82, natural degraded M = 3.64, human-mad degraded M = 3.09.

#### Scene dimensions

* Open vs. closed space
** Fear/anxiety in open spaces -

### DVs
#### Mood

* Positive affect
* Negative affect

#### Stress/Arousal

* Stress changes strongly correlated with negative affect changes (Rytir, 2011).

#### Cognitive capacity

* Berto (2005)
* Rees (2013)
* Lee et al. (2015).<ref name="Lee2015">Lee, K. E., Williams, K. J., Sargent, L. D., Williams, N. S., & Johnson, K. A. (2015). 40-second green roof views sustain attention: The role of micro-breaks in attention restoration. Journal of Environmental Psychology, 42, 182-189.</ref>

#### Liking/Preference

* White et al. (2010) explicitly measured effect and arousal (i.e. asking participants to rate, on a scale from 1 to 10, how happy a picture made them feel). This method could be subject to demand characteristics where participants have heard of the restorative properties of natural scenes and answered their questions to suit what they had heard rather than what they had really experienced.

## UC studies

Several Honours Thesis in Psychology students at the University of Canberra has conducted research studies about the psychological aspects of viewing natural scenes since 2011, under the supervision of James Neill. These studies are briefly summarised as follows:

### Rytir (2011)
#### Pilot study

* A set of openly licensed photos were initially categorized using theories and previous research into "natural", "semi-natural", and "urban", using the general approach described in Pretty (2005) to assess the accuracy of photo categorization.
* Participants rated the photos on an:
** 11-point artificial-natural scale
** 11-point unpleasant-pleasant scale
* As a result, a final set of 60 images (20 in each category) were selected, seeking to:
** Maximise the artificial-natural scale score differences between the three categories.
** Minimise the unpleasant-pleasant scale differences between the three categories

#### Main study

* Examined the effect of viewing natural, semi-natural, and natural image sets on mood (positive affect and negative affect) and stress.
* Examined the role of "connectedness to nature" (CNS) to determine whether CNS predicted the effects of viewing images on changes in mood in stress.
* By and large, there were small to moderate positive effects of viewing more natural images on mood and stress and these effects did not relate to CNS. Thus, the health and well-being benefits of nature exposure do not appear to be dependent on one's sense of CNS.

### Schlesinger (2013)

* The effect of scene naturalness on the components of Attention Restoration Theory

### Rees (2013)

* The effect of image naturalness and preference on directed attention fatigue
* Based on Berto (2005)

### Goch (2014)

* The role of the five-factor model of personality in understanding the effects of viewing natural, semi-natural and artificial scenes on positive and negative affect

### O'Toole (2015)

* The effects of water-based natural images on anger, sadness, and stress

### Hunter (2016/2017)

* Psychological effects of environmental sounds and scenes

### Taylor (2018)

* Effects of resources in nature scenes, and connectedness to nature, on mood
* This study examined the extent to which availability of survival resources in nature scenes affects positive and negative moods.
* This study also considered a potential moderating role of connectedness to nature (CNS).
* N = 262; n = 144 (abundant); n = 118 (barren)
* A new set of openly licenses imaged images were collected and tested through a pilot study (aka Rytir, 2011)
* Participants completed measures of positive and negative affect and CNS, then viewed an 80-second slideshow which consisted of 20 images (either abundant or barren images)
* No change in positive affect for both conditions
* Small-moderate decrease in negative affect for both conditions
* CNS explained little to no variance

## Method
### Participants

* Participants for initial studies can be first-year psychology students.
* Whilst it could be helpful to conduct computer lab classes for data collection, this is somewhat restrictive and the research design should allow for people to access the digital package and to watch and experience in their own time and place (via online survey/internet). This context (lab vs. normal) may be important and probably should be tested in later studies.

### Image sources

* Wiki commons - we could create a special category e.g., commons:Category:Psychology of nature scenes
* Flickr - images with cc by a licenses can be imported to Wiki commons

### Presentation

* Create timed slide presentations, then screen record and upload to Wiki commons, youtube etc.
* Present using online survey software (e.g., Qualtrics which allows for timing of responses).
* Randomly allocate participants to different conditions

### Design

* The design could be between-subjects (e.g., one of the experimental stimuli per participant) or within-subjects (e.g., all stimuli per participant) or a mixed-design. This will depend partly on how long the measures are per exposure. A within-subjects design will probably be more powerful, but there may well be contamination/order effects to consider and a fully experimental design may be "purer".

## Journals

* Environment and Behavior - Author guidelines - Acceptance rate: 10%
* Evolutionary Psychology - Author guidelines
* Frontiers in Psychology - Author guidelines
* Health & Place - Author guidelines
* Journal of Environmental Psychology - Author guidelines - Acceptance rate: 25%
* Landscape Research - Author guidelines
* Psychology journals

## Related projects

* Landscape study
* Psychology and the environment (APS Special Interest Group)
* In urban neighbourhoods, more trees equals less crime (Lisa Raffensperger, April 5, Discover)
* Green skins project, Curtin University