The Psychophysiological Implications of Soundscape: A Systematic Review of Empirical Literature and a Research Agenda

Effects of different natural soundscapes on human psychophysiology in national forest park

Most of the current soundscape research content is limited to the discussion of the restoration effect of single-element soundscapes, but it is the combination of sounds that is common in outdoor activities, and there is no evidence that the restoration of natural soundscapes is better with multi-element combinations. In this study, the Zhangjiajie National Forest Park in China was used as the research object, and the physiological indices of the subjects were collected through electroencephalogram signals, and the POMS short-form psychological scale was used to understand the subjective psychological responses of the subjects to the soundscape. The results showed that (1) The psychophysiological restorative ability of the natural soundscape of the National Forest Park was confirmed, and the subjects' psychological and physiological indices changed significantly and positively after listening to each section of the natural soundscape (p = 0.001). (2) The restorative effect of the multi-natural sound combination was ranked first in the overall ranking of the five natural soundscapes, and the multi-natural sound combination did indeed provide better restorative effects than the single-element sounds. (3) Gender does not usually have a significant effect on the restoration effect, and only Windy Sound among the four single-element nature sound landscapes and one multi-element combination of nature sound landscapes showed a significant gender difference, so in general, the effect of gender on the restoration effect of nature sound landscapes is not significant. In terms of research methodology, this study used cluster analysis to cluster the five types of natural soundscapes according to psychological and physiological recovery ability, and used ridge regression to construct mathematical models of the psychological and physiological recovery of each of the four natural soundscapes. The study of human physiological and psychological recovery from different types of natural soundscapes in China's national forest parks will provide a basis for soundscape planning, design, and policy formulation in national forest parks.

Psychological and physiological effects of soundscapes: A systematic review of 25 experiments in the English and Chinese literature

The aim of this systematic review was to conduct a comprehensive and rigorous investigation of both psychological and physiological responses to, and audio-visual interactions with, soundscapes to present an overview of the current status and to provide suggestions for future research. Our literature search focused on empirical and quantitative studies of journal articles and gray literature in English and Chinese. This systematic review excluded literature related to pure music, religious sounds, humanistic sounds, historical sounds, medical research, and differences in materials used. The Joanna Briggs Institute's Checklist for Randomized Controlled Trials was used to assess the risk of bias in the included studies. Twenty-five studies were included, involving 1950 participants. The major findings of this systematic review were that: (1) there were significant associations between the psychological and physiological responses; (2) the audio-visual interaction affected the psychological and physiological responses; and (3) because of the high risk of bias of the included studies, interpretation of their findings should be cautious. Nevertheless, given that this systematic review has a higher level of evidence than a single study and the synthesized evidence identified in this review is aligned with the results of other studies, the studies reviewed herein together provide consistent evidence. Replications are important in empirical research to build trustworthy results. Future research should focus on the psychological responses of pleasantness, preference, tranquility, the eight semantic dimensions (ISO 12913-2:2018), and the 11 pairs of adjectives describing the soundscape (Ba et al., 2023) and the physiological responses of heart rate variability and salivary, and follow the CONSORT guidelines to improve the research quality. An integration of sensory modalities, environmental factors, contextual indicators, temporal data, demographic variables, socio-cultural factors, and psychological and physiological responses may provide deeper insights into how people experience and understand the acoustic environment in context.

The Influence of Everyday Acoustic Environments on the Challenging Behavior in Dementia: A Participatory Observation Study in Nursing Homes

Challenging behavior (CB) is a group of behaviors, reactions and symptoms due to dementia, which can be challenging for the caregivers. The study aims to research the influence of acoustics on CB in people with dementia (PwD). An ethnographic method was used to study the daily life of PwD in their nursing homes with a specific focus on how people react to everyday environmental sounds. Thirty-five residents were included in the sample based on purposeful, homogeneous group characteristics and sampling. Empirical data were collected using 24/7 participatory observations. The collected data were analyzed using a phenomenological-hermeneutical method: a naïve understanding, a structural analysis and a comprehensive understanding. The result shows that the onset of CB depends on whether the resident feels safe and is triggered by an excess or lack of stimuli. The excess or shortage of stimuli and whether and when it affects a person is personal. It depends on various factors, the person's state and the time of day, the nature of the stimuli, familiarity, or strangeness is also a determining factor for the onset and progression of CB. The results can form an essential basis for developing soundscapes to make the PwD feel safe and reduce CB.

Human Auditory Ecology: Extending Hearing Research to the Perception of Natural Soundscapes by Humans in Rapidly Changing Environments

Research in hearing sciences has provided extensive knowledge about how the human auditory system processes speech and assists communication. In contrast, little is known about how this system processes "natural soundscapes," that is the complex arrangements of biological and geophysical sounds shaped by sound propagation through non-anthropogenic habitats [Grinfeder et al. (2022). Frontiers in Ecology and Evolution. 10: 894232]. This is surprising given that, for many species, the capacity to process natural soundscapes determines survival and reproduction through the ability to represent and monitor the immediate environment. Here we propose a framework to encourage research programmes in the field of "human auditory ecology," focusing on the study of human auditory perception of ecological processes at work in natural habitats. Based on large acoustic databases with high ecological validity, these programmes should investigate the extent to which this presumably ancestral monitoring function of the human auditory system is adapted to specific information conveyed by natural soundscapes, whether it operate throughout the life span or whether it emerges through individual learning or cultural transmission. Beyond fundamental knowledge of human hearing, these programmes should yield a better understanding of how normal-hearing and hearing-impaired listeners monitor rural and city green and blue spaces and benefit from them, and whether rehabilitation devices (hearing aids and cochlear implants) restore natural soundscape perception and emotional responses back to normal. Importantly, they should also reveal whether and how humans hear the rapid changes in the environment brought about by human activity.

Impact of the Soundscape on the Physical Health and the Perception of Senior Adults in Senior Care Facilities

Purpose:

To explore the impact of different acoustic stimuli of varying sound pressure levels on physical responses and the perception of senior adults.

Background:

Noise-related health problems have been gaining increased attention as studies have shown an association with negative impacts on physiological parameters resulting in cardiovascular morbidity and mortality. However, a gap in knowledge exists in exploring the impact of exposure to sound recordings in the actual environment on physiological measurements.

Methods:

Five acoustic stimuli were recorded in real life and 120 senior adults listened to them in a sound treated room to analyze the impacts of low-, middle-, and high-decibel sounds on their heart rate, blood pressure, and perception. The physical responses, heart rate, and blood pressure were measured during the sound exposure, and questionnaires were administered afterward.

Results:

Exposure to different sounds resulted in fluctuations and an inconsistent trend in heart rate, systolic pressure, and diastolic pressure. According to the physical measures and subjective evaluations, sport sounds and traffic noise were given the lowest rating for preference, while music was perceived as the most comfortable.

Conclusions:

A sound pressure level below 55–65 dB(A) correlates with increased comfort and less increase in heart rate and blood pressure. Senior adults with normal hearing preferred and were most comfortable with music, while those with severe hearing impairment preferred entertainment sounds the most.

Active Indoor Soundscape Design: A Case Study of Ceramic Passive Amplifiers

Indoor soundscape research has developed rapidly in recent years, with the aim of improving the single indoor noise reduction method and people's acoustic comfort. However, practical solutions to promote the generation of positive indoor soundscapes are still insufficient. The purpose of this study was to explore the improvement effect of ceramic passive amplifiers on the indoor soundscape and the relationship between the improvement effect and different amplifier shapes. Objective sound pressure level (SPL) values and subjective soundscape perception were measured for 10 ceramic passive amplifiers based on the soundscape, mainly using a comparative method. Ten sample amplifiers were compared with the acoustic data of the original open-plan studio environment, and then with an electronic sound amplifier. The results show that ceramic passive amplifiers can improve the quality of the indoor soundscape by creating sound scenes with appropriate loudness. Regarding non-acoustic aspects, the shape and materials of ceramic passive amplifiers play a positive role in emotional guidance.

Tranquillity in Urban Classical Chinese Gardens and Modern Parks: The Effect of Natural and Contextual Features

Parks and green spaces are an integral part of many urban areas. Such spaces offer a variety of psychological, physical and social benefits promoting a stronger sense of community and allowing people to cope better with everyday stress. These parks are often designed to provide tranquillity for people, and it is now an emerging area of policy in the promotion of quality of life. Tranquillity is considered a natural asset. Although they are vital, tranquil spaces are under threat, and it is, therefore, important to identify and understand such places so that they can be further planned and managed for the benefits that they provide. This study conceptualises the understanding of tranquillity and determines the extent to which a tranquil environment can be achieved. The study identified six parks referred to as “modern parks (MPs)” and “classical Chinese gardens (CCGs)”. Three parks each are located in Hong Kong and Guangzhou. Questionnaires were used to ascertain the importance of tranquil areas and the contribution of park components towards tranquillity. This study investigates the contribution of park elements that include both natural and contextual features. Furthermore, park characteristics and park elements were similarly identified. There were clear differences between natural and contextual features in terms of their potential contribution towards park users’ perceived tranquillity. There is also a striking importance and potential contribution of contextual features within classical Chinese gardens in relation to perceived tranquillity. This study concludes that there is the need to continue to enhance the quality of park spaces with regard to fostering tranquillity in urban areas.

Music Literacy and Soundscape Perception: A Study Based on the Soundwalk Method of Soundscapes

To explore a method of promoting college aesthetic education through campus environments, the Aesthetic Education Center of the Beijing Institute of Technology Zhuhai (BITZH-AEC) used the soundwalk method of soundscapes to carry out an experiment on students’ soundscape perceptions on campus. Half of the students who participated in the experiment (n = 42) had musical instrument learning experience and musical literacy. The research work used conventional statistical analysis methods and “Soundscapy”, newly developed by the British soundscape research team, to process the experimental data. It was found that the soundscape perception evaluation of students with musical literacy was different from that of ordinary students. This included a difference in the overall evaluation of the three experimental areas and a difference in the degree of dispersion of the soundscape evaluation of all six experimental areas. The study also found that there was no correlation between the acoustic noise level and the students’ evaluations of soundscape perception. BITZH-AEC proposes that aesthetic educators should pay attention to the idea of inspiring students to stimulate cultural imagination through soundscape perception.

Effects of Soundscape on Flow State during Diabolo Exercise

“Soundscape” is defined as “an acoustic environment as perceived or experienced and/or understood by a person or people, in context.” The research focuses on the physical properties of sound, paying attention to the relationship between the soundscape and people. Sports provide a comprehensive context, including the athletes, their behavior, the environment, spectators, and other elements. Soundscape in sports has many important functions, such as indicating the movement process, promoting positive emotions, and enhancing the entertainment atmosphere. It is also related to the physical and mental health of people who are exercising. As a technical sport with multidimensional soundscape qualities, diabolo is very popular among older adults in China due to its easy portability and operation. In order to explore the influence mechanism of the soundscape on the mental health of older players and better guide the shaping of soundscapes at sports venues, this paper focuses on soundscape perception and proposes a two-channel (direct and indirect) model of the influence of the diabolo soundscape on the psychological perception of older players. At the same time, we introduce the flow state as an indicator to evaluate mental health, and use the Short Flow State Scale (SFSS) to measure the flow state. By setting up a control experiment using the diabolo with and without sound and using the two-channel (direct and indirect) influence model to compare the differences in flow state scores under the two states, we analyzed the influence mechanism of the diabolo soundscape on the flow state of elderly groups. The results show that the scores of various flow state dimensions and total flow scores in the silent state of diabolo exercise are significantly lower than those in the sound state (p < 0.05 and p < 0.001), and the main differences are in the three dimensions of unambiguous feedback, sense of control, and autotelic experience. The two-channel influence model can effectively explain the differences in older adults’ flow state, which provides a new comprehensive perspective to study the effect of the soundscape in sports on people’s mental health.

Psychophysiological Impacts of Traffic Sounds in Urban Green Spaces

The goal of this study is to investigate the psychophysiological effects of traffic sounds in urban green spaces. In a laboratory experiment, psychological and physiological responses to four traffic sounds were measured, including road, conventional train, high-speed train, and tram. The findings demonstrated that traffic sounds had significant detrimental psychological and physiological effects. In terms of psychological responses, the peak sound level outperformed the equivalent sound level in determining the psychological impact of traffic sounds. The physiological effects of traffic sounds were shown to be significantly influenced by sound type and sound level. The physiological response to the high-speed train sound differed significantly from the other three traffic sounds. The physiological effects of road traffic sounds were found to be unrelated to the sound level. On the contrary, as for the railway sounds, the change in sound level was observed to have a significant impact on the participants’ physiological indicators.

Religious Belief-Related Factors Enhance the Impact of Soundscapes in Han Chinese Buddhist Temples on Mental Health

In contemporary society, mental health issues have received increasing attention. Moreover, how people perceive the acoustic environment affects mental health. In religious places, the unique religious soundscape, composed of the acoustic environment and sounds, has an obvious effect on mental health. In China, Han Chinese Buddhism has a long history and is currently the religion with the largest number of believers. The soundscape of temples has always been an important component of creating a Buddhist atmosphere. For this study, questionnaires were distributed to believers and tourists inside and outside several well-known Han Chinese Buddhist temples in China to analyse the relationship between evaluations of temple soundscapes (including the overall acoustic environment and preferences for typical sounds) and mental health and the role of religious belief-related factors in this relationship. The results indicated that for the respondents, the overall acoustic environment of Buddhist temples was significantly correlated with mental health and that a preference for three sounds in Buddhist temples, i.e., bells, wind chimes and chanting sounds, was significantly correlated with mental health. Among religious belief-related factors, attitudes toward Buddhist thought, frequency of temple visitation and purpose for visiting temples can affect the correlation between personal evaluations of temple soundscapes and mental health. For people who partially believe in Buddhist thought, people who visit Buddhist temples twice or less per year, or people who visit temples for tourism purposes, the correlations between evaluations of the overall acoustic environment and mental health are higher than for people without these religious characteristics. For people who fully believe in Buddhist thought or who visit temples neither to worship Buddha nor for tourism purposes, the correlations between the preferences for bells and wind chimes and mental health are higher than for people without these religious characteristics. For people who partially believe in Buddhist thought, the correlation between the preference for chanting and mental health is higher than for people with other attitudes toward Buddhist thought.

Indoor soundscapes at home during the COVID-19 lockdown in London - Part II: A structural equation model for comfort, content, and well-being

The present work constitutes the sequel to the analysis of data from an online survey administered to 464 home workers in London in January 2021 during the COVID-19 lockdown. Perceived affective quality of indoor soundscapes has been assessed in the survey through a previously developed model, as the combination of two perceptual dimensions, one related to comfort (a comfortable - annoying continuum) and the other to content (a full of content - empty continuum). Part I of the study reported on differences in comfort, content, and soundscape appropriateness based on the activity performed at home during the lockdown, i.e. working from home (WFH) and relaxation. Moreover, associations between soundscape dimensions and psychological well-being have been highlighted. Part II of the study deals with the exploration of the influences of several acoustical, building, urban and person-related factors on soundscape dimensions and well-being. A mixed-method approach has been adopted by combining multivariate regression of questionnaire scores with the qualitative analysis of spontaneous descriptions given by respondents. Results showed that several sound sources, urban features, housing characteristics, working modes and demographic factors can influence (positively and negatively) soundscape dimensions differently depending on the task at hand. Notably, the perceived dominance of neighbours' noises during relaxation, moderated by noise sensitivity, and the number of people at home were common factors negatively affecting both comfort and well-being, that partially explained the association between comfortable indoor soundscapes and better mental health. The discussion points out the importance of considering the different impacts that acoustical factors (e.g. sound typology), building (e.g., house size), urban (e.g., availability of a quiet side), situational (e.g., number of people at home), and person-related factors (e.g., noise sensitivity) can provide on building occupants depending on the specific activity people are engaged with at home and the opportunities to foster people's well-being through building, urban and acoustic design.

Effect of Road and Railway Sound on Psychological and Physiological Responses in an Office Environment

The present study aims to explore the psychophysiological impact of different traffic sounds in office spaces. In this experiment, 30 subjects were recruited and exposed to different traffic sounds in a virtual reality (VR) office scene. The road traffic sound and three railway sounds (conventional train, high-speed train, and tram) with three sound levels (45, 55, and 65 dB) were used as the acoustic stimuli. Physiological responses, electrodermal activity (EDA) and heart rate (HR) were monitored throughout the experiment. Psychological evaluations under each acoustic stimulus were also measured using scales within the VR system. The results showed that both the psychological and the physiological responses were significantly affected by the traffic sounds. As for psychological responses, considerable adverse effects of traffic sounds were observed, which constantly increased with the increase in the sound level. The peak sound level was found to have a better performance than the equivalent sound level in the assessment of the psychological impact of traffic sounds. As for the physiological responses, significant effects of both the acoustic factors (sound type and sound level) and the non-acoustic factors (gender and exposure time) were observed. The relationship between sound level and physiological parameters varied among different sound groups. The variation in sound level hardly affected the participants’ HR and EDA when exposed to the conventional train and tram sounds. In contrast, HR and EDA were significantly affected by the levels of road traffic sound and high-speed train sound. Through a correlation analysis, a relatively weak correlation between the psychological evaluations and HR was found.

Indoor soundscapes at home during the COVID-19 lockdown in London - Part I: Associations between the perception of the acoustic environment, occupantś activity and well-being

Since the outbreak of the COVID-19 pandemic, as a result of the adoption of worldwide lockdown measures, the home environment has become the place where all the daily activities are taking place for many people. In these changed social and acoustical contexts, we wanted to evaluate the perception of the indoor acoustic environment in relation to traditional and new activities performed at home, i.e., relaxation, and working from home (WFH). Taking London as a case study, the present paper presents the results of an online survey administered to 464 home workers in January 2021. The survey utilized a previously developed model for the assessment of indoor soundscapes to describe the affective responses to the acoustic environments in a perceptual space defined by comfort (i.e. how comfortable or annoying the environment was judged) and content (i.e., how saturated the environment is with events and sounds) dimensions. A mixed-method approach was adopted to reinforce result validity by triangulating data from questionnaires and spontaneous descriptions given by participants. In this first part of the study, the main objectives were: (1) evaluating differences in soundscape evaluation, in terms of comfort and content dimensions, based on the activity performed at home, (2) identifying appropriate conditions for WFH and relaxation, and (3) investigating associations between psychological well-being and indoor soundscapes. The results showed that the environments were perceived as more comfortable and slightly fuller of content when rated in relation to relaxation than for WFH, thus suggesting a stricter evaluation of the acoustic environment in the latter case. As regards the second objective, spaces that were more appropriate for relaxation had high comfort, whereas spaces appropriate for WFH resulted more private and under control, i.e. with high comfort and low content scores. Lastly, better psychological well-being was associated with more comfortable soundscapes, both for WFH (r_s = 0.346, p < .0005), and relaxation (r_s = 0.353, p < .0005), and with lower content while WFH (r_s = -0.133, p = .004). The discussion points out the need of considering the implications of changed working patterns to rethink the design of soundscapes in residential buildings, also in relation to potential well-being outcomes that will be further investigated in the Part II of the study.

A Proposal for a Data-Driven Approach to the Influence of Music on Heart Dynamics

Electrocardiographic signals (ECG) and heart rate viability measurements (HRV) provide information in a range of specialist fields, extending to musical perception. The ECG signal records heart electrical activity, while HRV reflects the state or condition of the autonomic nervous system. HRV has been studied as a marker of diverse psychological and physical diseases including coronary heart disease, myocardial infarction, and stroke. HRV has also been used to observe the effects of medicines, the impact of exercise and the analysis of emotional responses and evaluation of effects of various quantifiable elements of sound and music on the human body. Variations in blood pressure, levels of stress or anxiety, subjective sensations and even changes in emotions constitute multiple aspects that may well-react or respond to musical stimuli. Although both ECG and HRV continue to feature extensively in research in health and perception, methodologies vary substantially. This makes it difficult to compare studies, with researchers making recommendations to improve experiment planning and the analysis and reporting of data. The present work provides a methodological framework to examine the effect of sound on ECG and HRV with the aim of associating musical structures and noise to the signals by means of artificial intelligence (AI); it first presents a way to select experimental study subjects in light of the research aims and then offers possibilities for selecting and producing suitable sound stimuli; once sounds have been selected, a guide is proposed for optimal experimental design. Finally, a framework is introduced for analysis of data and signals, based on both conventional as well as data-driven AI tools. AI is able to study big data at a single stroke, can be applied to different types of data, and is capable of generalisation and so is considered the main tool in the analysis.

Sound and Soundscape in Restorative Natural Environments: A Narrative Literature Review

Acoustic experiences of nature represent a growing area in restorative environments research and are explored in this narrative literature review. First, the work surveyed indicates that nature is broadly characterized by the sounds of birdsong, wind, and water, and these sounds can enhance positive perceptions of natural environments presented through visual means. Second, isolated from other sensory modalities these sounds are often, although not always, positively affectively appraised and perceived as restorative. Third, after stress and/or fatigue nature sounds and soundscapes can lead to subjectively and objectively improved mood and cognitive performance, as well as reductions in arousal, although some inconsistencies in findings are observed. Fourth, theoretical frameworks of restorative environments would benefit from inclusion of acoustic environmental properties such as sound intensity or frequency. Fifth, findings regarding positive, learned semantic associations with nature have arisen as a result of recent work on sounds and restoration. This represents another important area of potential theoretical development for broader restorative environments research.

A synthesis of health benefits of natural sounds and their distribution in national parks

Parks are important places to listen to natural sounds and avoid human-related noise, an increasingly rare combination. We first explore whether and to what degree natural sounds influence health outcomes using a systematic literature review and meta-analysis. We identified 36 publications examining the health benefits of natural sound. Meta-analyses of 18 of these publications revealed aggregate evidence for decreased stress and annoyance (g = -0.60, 95% CI = -0.97, -0.23) and improved health and positive affective outcomes (g = 1.63, 95% CI = 0.09, 3.16). Examples of beneficial outcomes include decreased pain, lower stress, improved mood, and enhanced cognitive performance. Given this evidence, and to facilitate incorporating public health in US national park soundscape management, we then examined the distribution of natural sounds in relation to anthropogenic sound at 221 sites across 68 parks. National park soundscapes with little anthropogenic sound and abundant natural sounds occurred at 11.3% of the sites. Parks with high visitation and urban park sites had more anthropogenic sound, yet natural sounds associated with health benefits also were frequent. These included animal sounds (audible for a mean of 59.3% of the time, SD: 23.8) and sounds from wind and water (mean: 19.2%, SD: 14.8). Urban and other parks that are extensively visited offer important opportunities to experience natural sounds and are significant targets for soundscape conservation to bolster health for visitors. Our results assert that natural sounds provide important ecosystem services, and parks can bolster public health by highlighting and conserving natural soundscapes.

Revisiting the Concept of Quietness in the Urban Environment-Towards Ecosystems' Health and Human Well-Being

There is plenty of proof that environmental noise is a major pollutant in the urban environment. Several approaches were successfully applied for its calculation, visualization, prediction and mitigation. The goal of all strategy plans regards its reduction and the creation of quietness. This study aims to revisit the concept of quietness in the urban environment and attempts to portray a new understanding of the specific phenomena. "Quietness" as a term retains an ambiguity, and so far, it can be described as the lack of something, meaning the lack of noise that is portrayed by means of intensity. Several studies describe quietness as the combination of perceptual soundscape elements and contextual factors that can be quantified, combined, weighed and used as indicators of healthy soundscapes. In this research, the focus is on setting aside all indicators, either measuring the intensity or contextual ones and use solely quantifiable metrics regarding the acoustic environment, thus introducing a new composite index called the composite urban quietness index (CUQI). After testing the CUQI, in order to verify the results of previous research regarding the identification of quiet Areas in the city of Mytilene (Lesbos Island, Greece), the study concludes that CUQI is efficiently functioning even in this early stage of development.

Perceived biodiversity, sound, naturalness and safety enhance the restorative quality and wellbeing benefits of green and blue space in a neotropical city

Urban land cover expansion and human population growth are accelerating worldwide. This is resulting in the loss and degradation of green and blue spaces (e.g. parks, waterways, lakes) in cities, which provide resources to sustain biodiversity and improve human wellbeing. The specific characteristics of these spaces (e.g. sounds, species, safety) that enhance or detract from wellbeing are underexplored, yet this knowledge is needed to inform urban planning, management and policies that will ultimately benefit both people and biodiversity. Research of this kind is rarely conducted in the Global South, where rapid urbanisation threatens biodiversity-rich ecosystems of worldwide significance. Here, we examine how perceptions of green, waterway, and dense urban spaces relate to wellbeing in Georgetown, Guyana. Specifically, we use mediation models to test how perceptions of sound, bird species richness, naturalness, and safety concerns contribute to sites being perceived as restorative which, subsequently, influences wellbeing. We assess the accuracy of these site perceptions with objective measures of sound (using a bioacoustic sound index), bird species richness, and percent coverage of vegetation, water, and impervious surfaces. Results showed that if sites were perceived as species rich, containing natural sounds like birdsong, natural rather than artificial, and safe, they were perceived as more restorative, resulting in improved wellbeing. In general, people's perceptions were consistent with objective measures. Green, compared with waterway and dense urban sites, contained more biophonic sounds, higher species richness, greater vegetation and water coverage. Although waterways were biodiverse, they were dominated by anthrophonic sounds, so were perceived as artificial and non-restorative. We shed light on how city planners might augment specific characteristics to improve the wellbeing of urban dwellers, with implications for biodiversity conservation. Our findings provide a scientific evidence base for urban design and management plans that could deliver multiple co-benefits, particularly in biodiversity-rich cities in neotropical regions.

Confinement and the Hatred of Sound in Times of COVID-19: A Molotov Cocktail for People With Misophonia

Forced strict confinement to hamper the COVID-19 pandemic seriously affected people suffering from misophonia (M+) and those living with them. Misophonia is a complex neurophysiological and behavioral disorder of multifactorial origin, characterized by an intense physiological and emotional response produced by intolerance to auditory stimuli of the same pattern, regardless of physical properties. The present work studied the secondary impact that strict confinement caused in 342 adults (224 women: 118 men) regularly attending a medical psychological center in Barcelona. Misophonia, usually underdiagnosed, showed a prevalence of 35%, the same for women (37%) than men (31%). A retrospective analysis using a physical-psychological-social inventory of 10 variables evaluated the number of individuals that during confinement and self-confinement (March 11 - June 29, 2020) canceled (mostly M-) and/or requested a therapeutic intervention, the reasons for their request, and the strategies they used to self-manage the situation. Ten main variables indicated that the confinement exponentially increased the effects of misophonia compared with results from the same individuals during the last quarter of 2019. Most people diagnosed with misophonia continued with tele-assistance during the confinement because of this impact's self-concern. Besides the impacts as part of the general population, M+ also developed different symptoms causing significant personal, social, and job/occupational imbalance, as compared to M-. Health, fears, conflicts with neighbors, study-related difficulties were outstanding reasons for consultations. The LSB-50 test for 'Psychological and Psychosomatic Symptoms' applied to M+ revealed the increase of 8 of 9 items of this psychopathological test. Sleep disorders (coronasomnia), hostility, depression, and somatization were more severe than in previous assessments. Women presented the worst psychological and psychosomatic states (eight out of nine, as compared to one out of nine in males). The study unveiled the complex physical-psychological-social burden, the need for dissemination and a gender perspective to understand the secondary impact of COVID-19 pandemic on the mental health of the population with misophonia. The results also show that in this new COVID era people suffering from misophonia need to develop coping strategies addressing modifiable risk and protective factors. They deserve familial/social comprehension, stronger clinical support and a gender medicine perspective.

Sounds of Silence in Times of COVID-19: Distress and Loss of Cardiac Coherence in People With Misophonia Caused by Real, Imagined or Evoked Triggering Sounds

The extreme, unprecedented situations in the current COVID-19 pandemic are risk factors for psychosocial stress for the entire population. However, strict confinement had a particular impact on people suffering from misophonia and their families. Misophonia is a condition in which hearing certain sounds triggers intense anger, disgust and even severe autonomic nervous system responses. This prospective cohort study examined the impact of strict confinement (Spain, March 14-June 21, 2020) on a sample of 24 people (16 women and eight men) who had been diagnosed with moderate to extreme misophonia and were regularly attending a medical psychology center in Barcelona. The 3-month period of confinement caused general emotional maladjustment, distress, and a transitory crisis. Long-term biomonitoring of their heart variability rate (HRV) enabled to identify a significant increase in physiological arousal after the confinement period, which had already been recorded in a loss of cardiac coherence under basal rest/relaxation conditions. Certain auditory stimuli triggered adverse responses, lowered HRV scores, and an increased stress level and heart rate. Loss of cardiac coherence in their responses to these auditory stimuli (triggering mouth, nose and other sounds), as well as to non-triggering mouth, nose and other sounds was increased when compared to two assessments performed during the previous year. Despite the limited sample size, sex differences were observed in the incidence. Loss of cardiac coherence worsened with the severity of the misophonia. Most importantly, imagined or evoked triggering sounds, as well as real ones, were enough to cause the aversive responses, as displayed by the increased loss of cardiac coherence with respect to the at-rest basal level. A semi-structured interview revealed the exceptional nature of the situations, increased hyper-sensorial sensitivity, fear of being infected with or dying from COVID-19, the patients' coping strategies, and the difficulties and constraints they faced. Finally, the article gives recommendations for better management of misophonia. Improved knowledge of this disorder would help address the current lack of health and social care, hopefully preventing this shortfall's impact on social and affective relationships, which are particulary important for well-being now and in the coming periods of physical distancing measures.

Audiovisual Bimodal and Interactive Effects for Soundscape Design of the Indoor Environments: A Systematic Review

A growing number of soundscape studies involving audiovisual factors have been conducted; however, their bimodal and interactive effects on indoor soundscape evaluations have not yet been thoroughly reviewed. The overarching goal of this systematic review was to develop the framework for designing sustainable indoor soundscapes by focusing on audiovisual factors and relations. A search for individual studies was conducted through three databases and search engines: Scopus, Web of Science, and PubMed. Based on the qualitative reviews of the selected thirty papers, a framework of indoor soundscape evaluation concerning visual and audiovisual indicators was proposed. Overall, the greenery factor was the most important visual variable, followed by the water features and moderating noise annoyance perceived by occupants in given indoor environments. The presence of visual information and sound-source visibility would moderate perceived noise annoyance and influence other audio-related perceptions. Furthermore, sound sources would impact multiple perceptual responses (audio, visual, cognitive, and emotional perceptions) related to the overall soundscape experiences when certain visual factors are interactively involved. The proposed framework highlights the potential use of the bimodality and interactivity of the audiovisual factors for designing indoor sound environments in more effective ways.

Listening to Forests: Comparing the Perceived Restorative Characteristics of Natural Soundscapes before and after the COVID-19 Pandemic

Natural sounds are known to contribute to health and well-being. However, few studies have investigated what makes a natural sound renew and re-energize people, especially in the face of significant stressors caused by the Corona Virus Disease 2019 (COVID-19). This study examined the interactive mechanism towards the perceived restorative characteristics of natural soundscapes: fascination, being-away, compatibility, and extent. Two groups of data were collected in Burleigh Heads National Park, Australia, before the outbreak of COVID-19 (n = 526) and in October 2020 (n = 371). The objective measures of LAeq confirmed that the acoustic environment of Burleigh Heads National Park are quiet and peaceful for attention restoration. The results of the subject evaluation revealed that participants from the post-COVID-19 group reported higher stress levels, while there was a greater mental restoration through water sounds. There are significant differences between the pre- and post-COVID-19 groups with respect to the relationships among the perceived restorative characteristics of natural soundscapes. The direct effects of extent and fascination, as well as the mediating effects of fascination, were more significant among the post-COVID-19 group than the pre-COVID-19 group. However, the effects of being-away on compatibility were less significant in the post-COVID-19 group. This study reduces the gap that exists on the research of environment–people–health–wellbeing nexus. Knowledge about natural soundscapes encourages administrations to consider it as a guideline for the planning and management of natural resources, especially during the COVID-19 pandemic.

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

Natural environments have been shown to trigger psychological and physiological restoration in humans. A new framework regarding natural environments restorative properties is proposed. Conditioned restoration theory builds on a classical conditioning paradigm, postulating the occurrence of four stages: (i) unconditioned restoration, unconditioned positive affective responses reliably occur in a given environment (such as in a natural setting); (ii) restorative conditioning, the positive affective responses become conditioned to the environment; (iii) conditioned restoration, subsequent exposure to the environment, in the absence of the unconditioned stimulus, retrieves the same positive affective responses; and (iv) stimulus generalization, subsequent exposure to associated environmental cues retrieves the same positive affective responses. The process, hypothetically not unique to natural environments, involve the well-documented phenomenon of conditioning, retrieval, and association and relies on evaluative conditioning, classical conditioning, core affect, and conscious expectancy. Empirical findings showing that restoration can occur in non-natural environments and through various sensory stimuli, as well as findings demonstrating that previous negative experience with nature can subsequently lower restorative effects, are also presented in support of the theory. In integration with other existing theories, the theory should prove to be a valuable framework for future research.

Acoustics for Supportive and Healthy Buildings: Emerging Themes on Indoor Soundscape Research

The focus of the building industry and research is shifting from delivering satisfactory spaces to going beyond what is merely acceptable with a wave of new research and practice dedicated to exploring how the built environment can support task performance and enhance people’s health and well-being. The present study addresses the role of acoustics in this paradigm shift. Indoor soundscape research has recently emerged as an approach that brings a perceptual perspective on building and room acoustics in order to shape built environments that “sound good” according to building occupants’ preference and needs. This paper establishes an initial discussion over some of the open questions in this field of research that is still in an embryonic stage. A thematic analysis of structured interviews with a panel of experts offered a range of perspectives on the characterization, management, and design of indoor soundscapes and health-related outcomes. The discussion pointed out the importance of both perceptual and multisensory research and integrated participatory design practices to enable a holistic view regarding the complex building–user interrelations and the design of just cities. Soundscape methodologies tailored to the peculiarities of indoor soundscapes can help to measure and predict the human perceptual response to the acoustic stimuli in context, thus reducing the risk of mismatches between expected and real building experiences. This perceptual perspective is expected to widen the scientific evidence for the negative and positive impacts of the acoustic environment on human health, well-being, and quality of life. This will support prioritizing the role of acoustics in building design and challenge many current design practices that are based on a noise control approach.

MacIntyre T, Calogiuri G. Enable, Reconnect and Augment: A New ERA of Virtual Nature Research and Application

Being exposed to natural environments is associated with improved health and well-being, as these environments are believed to promote feelings of “being away” from everyday struggles, positive emotional reactions and stress reduction. Despite these positive effects, humanity is becoming increasingly more distanced from nature due to societal changes, such as increased urbanization and the reduced accessibility of natural environments. Technology is also partly to blame, as research suggests that people replace nature contact with increased screen time. In this cross-section between nature and technology, we find technological nature which is progressing towards a point where we may be capable of simulating exposure to real nature. Concerns have been raised regarding this technology, as it is feared it will replace real nature. However, research suggests that virtual nature may have a more positive impact on society than a mere replacement of real nature, and this review propose several areas where virtual nature may be a beneficial addition to actual nature (Enable), help people reconnect with the real natural world (Reconnect) and “boost” human-nature interactions (Augment). Based on the current research and theoretical framework, this review proposes guidelines for future research within these areas, with the aim of advancing the field by producing high quality research.

The Relationship between Different Types of Alarm Sounds and Children's Perceived Risk Based on Their Physiological Responses

Due to differences in cognitive ability and physiological development, the evacuation characteristics of children are different from those of adults. This study proposes a novel method of using wearable sensors to collect data (e.g., electrodermal activity, EDA; heart rate variability, HRV) on children’s physiological responses, and to continuously and quantitatively evaluate the effects of different types of alarm sounds during the evacuation of children. In order to determine the optimum alarm for children, an on-site experiment was conducted in a kindergarten to collect physiological data for responses to different types of alarm sounds during the evacuation of 42 children of different ages. The results showed that: (1) The alarm sounds led to changes in physiological indicators of children aged 3–6 years, and the effects of different types of alarm sounds on EDA and HRV activities were significantly different (p < 0.05). Skin conductance (SC), skin conductance tonic (SCT) and skin conductance level (SCL) can be used as the main indicators for analysing EDA of children in this experiment (p < 0.05), and the indicators of ultralow frequency (ULF) and very low frequency (VLF) for HRV were not affected by the type of alarm sounds (p > 0.05). (2) Unlike adults, kindergarten children were more susceptible to the warning siren. The combined voice and warning alarm had optimal effects in stimulating children to perceive risk. (3) For children aged 3–6 years, gender had a significant impact on children’s reception to evacuation sound signals (p < 0.05): Girls are more sensitive than boys in receiving evacuation sound signals, similar to findings of studies of risk perception of adult males and females. In addition, the higher the age, the greater the sensitivity to evacuation sound signals, which accords with results of previous studies on the evacuation dynamics of children.

Assessment Methods and Factors Determining Positive Indoor Soundscapes in Residential Buildings: A Systematic Review

The design of an indoor acoustic environment positively perceived by building occupants requires a perceptual approach to be adopted in order to define what makes it sound good. Soundscape standards ISO 12913 have been introduced to assess how the acoustic environment is perceived, in context, by people. According to the standards, a straightforward characterization of a soundscape as positive is currently possible only through measurements by persons, because of a current gap in linking perceptual metrics to acoustic or psychoacoustic measurements. In addition, despite applying also to indoor contexts, methods and perceptual metrics described by the standards have been mainly derived from studies related to outdoor urban environments and it is not clear whether they could be directly applied indoor. For this reason, a systematic review was performed to investigate: (i) Data collection methods used in the literature for indoor residential soundscapes and (ii) factors, output of such methods, that characterize them positively. For this purpose, a systematic review has been conducted in accordance with the PRISMA guidelines (preferred reporting items for systematic reviews and meta-analyses) guidelines. The Scopus database was searched for peer-reviewed journal papers published in English, between 1 January 2009 and 24 June 2019, including: (1) field or laboratory studies relevant to residential buildings and (2) studies assessing factors that influence the perception by building users of indoor acoustic environments. The search excluded studies related to: (a) Speech perception issues; (b) noise-induced sleep disturbance; (c) acoustic perception by hearing impaired building users; (d) perception of vibrations or impact sounds. The search returned 1087 results. After the screening process, 37 articles were finally included. Given the differences in methodologic approaches, a quantitative meta-analysis could not be performed, and a qualitative approach was adopted instead. A large part of the selected literature reflected a general effort of minimizing noise annoyance by reducing noise exposure and, in particular, noise levels. Questionnaires and guided interviews were used to capture people’s perception, while the adoption of soundwalks and non-participatory behavioral studies did not emerge in the review literature and need further investigation. The evaluation of a variety of auditory sensations both in their positive and negative dimensions, beyond annoyance, would be required to explore the positive perceptual potential of sounds. Besides sound level, a variety of factors related and unrelated to the acoustic environment were found to affect perceptual outcomes and a framework of evaluation has been proposed as a reference for future assessments. Results encourage the integration of soundscape methodologies into IEQ research, in order to enhance user health and well-being.