Proposing a Framework for the Restorative Effects of Nature through Conditioning: Conditioned Restoration Theory

Combining hierarchical drift-diffusion model and event-related potentials to reveal how do natural sounds nudge green product purchases

Sound is one of the important environmental factors that influence individuals' decision-making. However, it is still unclear whether and how natural sounds nudge green product purchases. This study proposes an extension of the Stimulus-Organism-Response (S-O-R) framework, suggesting that natural sounds increase early attentional congruency associated with green products, thereby promoting individuals' green product purchases. To test our theory, we conducted an experiment employing a hierarchical drift-diffusion model (HDDM) and utilized an event-related potentials (ERP) method. Results showed that natural sounds not only increased the purchase rate for green products but also enhanced drift rate in favor of purchasing green products. Additionally, consumers also exhibited a reduced frontal early P2 wave (150-230 ms) in response to green products under natural sounds, indicating that natural sounds increased the early attentional congruency associated with green products. More importantly, neural correlates of early attentional congruency meditated the nudge effect of natural sounds on purchase rate and drift rate for green products. This study contributes to the neural understanding of how natural sounds influence green product purchases and provides actionable implications for market managers to design the green products sales environments.

Watching (natural) beauty boosts task performance: testing the nature-as-reward hypothesis

In two online studies, we tested the "nature-as-reward hypothesis", which suggests that superior cognitive task performance following nature exposure reflects a general performance improvement, driven by the reward value of beautiful things. In both between-subjects experiments, participants viewed either beautiful or less beautiful images for 10 s, comprising beautiful mountain photos (vs. less beautiful mountain drawings) in Study 1 and beautiful fractals (vs. less beautiful pixelated images) in Study 2. Following image exposure, participants engaged in a ticking task requiring them to freely tick up to 200 boxes. Participants had to complete four (Study 1) or five (Study 2) of such ticking tasks, with each task being preceded by either a beautiful or less beautiful image. In Study 1, for a subset of participants the ticking task was framed as a game. We found that in Study 1, ticking declined over the ticking rounds when participants had viewed less beautiful line drawings of mountains, while ticking performance remained unchanged over the rounds after seeing beautiful mountain images. However, when the ticking task was framed as a game, there was no significant difference in ticking performance between the two beauty conditions over the four ticking rounds. In Study 2, participants ticked more boxes over all ticking rounds after viewing images of beautiful fractals compared to less beautiful pixelated images. In line with the nature-as-reward hypothesis, these findings show that brief exposures to beautiful (nature) images can motivate to work and that framing tasks as a game can attenuate this beauty advantage.

Impact of exposure to natural versus urban soundscapes on brain functional connectivity, BOLD entropy and behavior

BACKGROUND

Humans have been moving from rural to urban environments for decades. This process may have important consequences for our health and well-being. Most previous studies have focused on visual input, and the auditory domain has been understudied so far. Therefore, we set out to investigate the influence of exposure to natural vs urban soundscapes on brain activity and behavior.

METHODS

Resting-state fMRI data was acquired while participants (N = 35) listened to natural and urban soundscapes. Two affective questionnaires (the Positive and Negative Affect Schedule (PANAS) and the Perceived Stress Scale) and two cognitive tasks (dual n-back (DNB) and the backward digit-span (BDS)) were assessed before and after each soundscape condition. To quantify brain function we used complexity and network measures, namely brain entropy (BEN) and whole brain functional connectivity (FC). To study the link between brain and behavior, changes in BEN and whole brain FC were correlated to changes in cognitive performance and self-reported affect.

RESULTS

We found higher BEN when listening to urban sounds in posterior cingulate gyrus, cuneus and precuneus, occipital lobe/calcarine as compared to nature sounds, which was negatively correlated to (post-pre) differences in positive affect (PANAS) in the urban soundscape condition. In addition, we found higher FC between areas in the auditory, cinguloopercular, somatomotor hand and mouth networks when listening to nature as compared to urban sounds which was positively correlated to (post-pre) differences of the of the composite score of Digit span and N-back for nature soundscape.

CONCLUSIONS

This study provides a framework for the neural underpinnings of how natural versus urban soundscapes affect both whole brain FC and BEN and bear implications for the understanding of how the physical auditory environment affects brain function and subsequently observed behavior. Moreover, correlations with cognition and affect reveal the meaning that exposure to soundscapes may have on the human brain. To the best of our knowledge this is the first study to analyze BEN and whole brain FC at rest during exposure to nature and urban soundscapes and to explore their relationship to behavior.

How can plant-enriched natural environments benefit human health: a narrative review of relevant theories

Plant-enriched environments, the most common terrestrial landscapes, are usually coded as "green space" in urban studies. To understand how these natural environments can benefit human health, many theories have been developed, such as the well-known Attention Restoration Theory. Nowadays, more theories are emerging with regard to various and complex health dimensions. In this context, we searched online databases (from 2000 to 2022) and conducted a narrative review aiming to introduce relevant theories concerning psychological (e.g. Perceptual Fluency Account and Conditioned Restoration Theory), physiological (e.g. volatile organic compounds and environmental microbiomes), and behavioural (e.g. physical activity and social contact) perspectives. We also slightly mentioned some limitations and directions to be considered when using these theories. These results may offer general readers insights into the value of nature exposure and also help relevant researchers with study design and result interpretation.

In situ psycho-cognitive assessments support self-determined urban green exercise time

Prescribed nature walks frequently yield improvements to mood and cognition as observed in experimental studies. Research that uses real life settings such as self-determined time exercising outdoors for restorative health benefits may more accurately elicit effects than time-specified study protocols. This study examined in situ psycho-cognitive outcomes of routine walks in urban greenspace to test the concept that self-set exposure duration and not context alone is related to magnitude of psycho-cognitive benefit. Pre-post measurements taken on a diverse participant pool of individuals walking in urban parks and recruited on random days over a two-week period found significant associations between outdoor activity duration and cognitive and mood improvements. Greater outdoor walking duration linearly predicted stronger processing speeds but non-linearly in tests of other cognitive domains. Results of fixed effects model for mean mood change following green exercise show outdoor walking influenced mood change at highest levels of significance, even after accounting for individual level variability in duration. Mood improved for all durations of outdoor walking under a random effects model with high significance. Untethering fixed intervals of outdoor exercise from formal study design revealed briefer but more frequent nature engagement aligned with nature affinity. The influence of unmeasured factors, e.g., nature affinity or restorative conditioning, for prescriptive durations of urban green exercise merits further investigation toward designing wellbeing interventions directed at specific urban populations.

Seasonal Variations in the Effectiveness of Immersive Virtual Nature

AIM

The aim of this study was to assess whether the outcomes of immersive virtual nature (IVN) varies between seasons.

BACKGROUND

IVN has received increased interest in recent years due to its potential applications within health and design. However, factors influencing people's responses to IVN are largely unknown. Seasons affect a variety of human processes and behaviors including levels of affect and blood pressure, also in the context of human-nature interactions. These seasonal variations might influence how people interact and respond to IVN, especially since IVN allow for representations of nature that are not representative of the current real-life season.

METHODS

A secondary analysis of data retrieved from two previous studies, which included three IVN conditions, was conducted. All IVNs represented late spring conditions. Measures included perceived environmental restorativeness, affect, enjoyment, heart rate, and blood pressure. A meta-analytic approach was used to assess whether there were consistent differences between participants who were exposed to the IVN in spring/summer (early June to mid-September) and autumn/winter (mid-September to December) across the three different conditions.

RESULTS

There was a consistent effect of season only for one component of affect (fatigue), with larger reductions in fatigue when exposed to IVN during autumn/winter compared to spring/summer. No other significant effects of season were observed.

CONCLUSION

IVNs are feasible to use across all seasons but might be more effective in reducing the feeling of fatigue during autumn and winter compared to other seasons.

Mental imagery of nature induces positive psychological effects

Exposure to natural environments promotes positive psychological effects. Experimental studies on this issue typically have not been able to distinguish the contributions of top-down processes from stimulus-driven bottom-up processing. We tested in an online study whether mental imagery (top-down processing) of restorative natural environments would produce positive psychological effects, as compared with restorative built and non-restorative urban environments. The participants (n = 70) from two countries (Finland and Norway) imagined being present in different environments for 30 s, after which they rated their subjective experiences relating to vividness of imagery, relaxation, emotional arousal, valence (positivity vs. negativity) of emotions, and mental effort. In addition, a psychometric scale measuring vividness of imagination, a scale measuring nature connectedness, and a questionnaire measuring preference of the imagined environments were filled-in. Imagery of natural environments elicited stronger positive emotional valence and more relaxation than imagery of built and urban environments. Nature connectedness and preference moderated these effects, but they did not fully explain the affective benefits of nature. Scores in a psychometric imagery scale were associated in consistent way to the subjective ratings in the imagery task, suggesting that the participants performed attentively and honestly in reporting their subjective experiences. We conclude that top-down factors play a key role in the psychological effects of nature. A practical implication of the findings is that inclusion of natural elements in imagery-based interventions may help to increasing positive affective states.

A Systematic Review of Mechanisms Underpinning Psychological Change Following Nature Exposure in an Adolescent Population

This systematic review aimed to identify mechanisms of psychological change following exposure to nature within an adolescent population. Keyword searches within Scopus, PsychINFO and Web of Science were carried out to include articles published by 14 September 2021. Records were reviewed in line with inclusion criteria: samples with an average age of 24 and under, exposure to nature vs. control using an experimental or quasi-experimental design and outcomes of mental health and psychological status. The review resulted in 27 papers that were assessed for methodological quality and manually searched for mediation analyses. A range of psychological outcomes were identified and grouped into 10 categories: Mood and Affect, Mental Health, Wellbeing, Perceived Restoration, Stress, Energy, Cognitive Functioning, Resilience, Self-Concept and Pro-Social Behaviour. Only one formal mediation analysis was reported, highlighting a mediating role of belonging in increases in resilience. Limitations include the majority use of university student samples and over half of the papers being of low methodological quality. No firm conclusions on key mechanisms in an adolescent population were made due to insufficient evidence of mediating variables. The development of methodologically rigorous experimental studies with the inclusion of statistical pathway modelling is needed to test and specify plausible mechanisms.

Restoration Skills Training in a Natural Setting Compared to Conventional Mindfulness Training: Sustained Advantages at a 6-Month Follow-Up

Restoration skills training (ReST) is a mindfulness-based course in which participants draw support from a natural practice setting while they learn to meditate. Well-established conventional mindfulness training (CMT) can improve psychological functioning but many perceive it as demanding and fail to sustain practice habits. Applying non-inferiority logic, previous research indicated that ReST overcomes compliance problems without compromising the benefits gained over 5 weeks’ training. This article applies similar logic in a 6-month follow-up. Of 97 contacted ReST and CMT course completers, 68 responded and 29 were included with multiple imputation data. The online survey included questions about their psychological functioning in three domains (dispositional mindfulness, cognitive lapses, and perceived stress) and the forms and frequencies with which they had continued to practice mindfulness after the course. Former ReST participants continued, on average, to show higher dispositional mindfulness and fewer cognitive lapses compared to pre-course ratings. Improved psychological functioning in one or more domains was demonstrated by 35%, as determined by a reliable change index. Again, analyses detected no indications of any substantive disadvantages compared to the more demanding, established CMT approach. Compared to the CMT group, more ReST participants had also continued to practice at least occasionally (92 vs. 67%). Continued practice was linked to sustained improvements for ReST but not clearly so for CMT. ReST participants thus continued to use the skills and sustained the improvements in psychological functioning that they had gained in the course, further supporting the utility of ReST as a health intervention.

Watching Nature Videos Promotes Physiological Restoration: Evidence From the Modulation of Alpha Waves in Electroencephalography

Various lines of evidence have shown that nature exposure is beneficial for humans. Despite several empirical findings pointing out to cognitive and emotional positive effects, most of the evidence of these effects are correlational, and it has been challenging to identify a cause-effect relationship between nature exposure and cognitive and emotional benefits. Only few of the published studies use psychophysiological methods to assess the biological correlates of these positive effects. Establishing a connection between human physiology and contact with natural settings is important for identifying cause-effect relationships between exposure to natural environments and the positive effects commonly reported in connection to nature exposure. In the present study, we recorded physiological indexes of brain activity (electroencephalography) and sympathetic nervous system (electrodermal activity), while the participants were presented with a series of videos displaying natural, urban, or neutral (non-environmental, computerized) scenes. Participants rated the scenes for their perceived relaxing value, and after each experimental condition, they performed a cognitive task (digit span backward). Participants rated natural videos as the most relaxing. Spectral analyses of EEG showed that natural scenes promoted alpha waves, especially over the central brain. The results suggest that experiencing natural environments virtually produces measurable and reliable brain activity markers which are known to be related to restorative processes.

The Mediating Effect of Nature Restorativeness, Stress Level, and Nature Connectedness in the Association between Nature Exposure and Quality of Life

This study aimed to test the mediating effects of nature restorativeness, stress, and nature connectedness in the association between nature exposure and quality of life (QoL). Urban and rural Lithuanian inhabitants (n = 924; 73.6% were women), mean age of 40.0 ± 12.4 years (age range of 18–79) participated in the study. In total, 31% of the respondents lived in rural areas. Study participants completed an online survey form with measures on sociodemographic factors, nature proximity, nature exposure, nature connectedness, and nature restorativeness, stress, and QoL assessed by the abbreviated version of the World Health Organization’s Quality of Life Questionnaire’s (WHOQOL-BREF). Path analysis was conducted to test the mediating effects of nature restorativeness, stress, and nature connectedness in the model of nature exposure and QoL. Nature exposure was directly associated with a greater QoL (β = 0.14; B = 2.60; SE = 0.57; p < 0.001) and mediated the association between nature proximity and QoL. Nature restorativeness and lower stress levels were mediators between nature exposure and QoL. Nature connectedness was a mediator between nature exposure and QoL. A path model was invariant across genders and the urban and rural place of residence groups: patterns of loadings of the pathways were found to be similar. Nature restorativeness (β = 0.10–0.12; p < 0.01) had a positive effect on the psychological, physical, social, and environmental domains of QoL. Connectedness to nature positively predicted psychological (β = 0.079; p < 0.05) and environmental (β = 0.082; p < 0.05) domains of QoL. Enhancing nature exposure and nature connectedness might help strengthen QoL in urban and rural inhabitants.

The Value of Nature During Psychotherapy: A Qualitative Study of Client Experiences

Nature is considered to have restorative qualities that can potentially improve psychotherapy success. However, little is known about how clients experience nature during psychotherapy. The research aim of this phenomenological qualitative study was to study how clients experience nature during individual outpatient psychotherapy that took place while walking in nature. More specifically we were interested in clients’ inner world experiences. All participants (N = 12) received treatment through licensed therapists for a DSM-5 classified disorder. Semi-structured interviews were conducted. To uncover true lived experiences during these interviews, participants were asked to close their eyes and envision themselves during a psychotherapy session in nature. The verbatim transcripts were coded by means of inductive thematic analysis and the results were member checked. Results showed that nature brings clients closer to their inner worlds. How nature brings this about is unfolded in a conceptual model of lived experience. We argue that psychotherapy can be enriched by considering nature as a supportive environment because bringing clients closer to their inner worlds is of essential value in facilitating successful treatment interventions.