Next Article in Journal
Data Augmentation Using Multivariate Time Series Decomposition for Predicting Daily Energy Consumption of New Buildings
Previous Article in Journal
Automated Checking of Highway Bridge BIM Models Based on Large Language Models
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Buildings
Volume 15
Issue 19
10.3390/buildings15193466
buildings-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Calm by Design: Nature-Inspired Rooms Reduce Electrodermal Activity Levels

by
Mariachiara Rapuano
1,*,
Francesco Ruotolo
1,
Loreta Cannito
1,2,
Massimiliano Masullo
3,
Federico Cioffi
3,
Gennaro Ruggiero
1,
Luigi Maffei
3,
Fabiola Capitelli
1 and
Tina Iachini
1
1
Department of Psychology, University of Campania “L. Vanvitelli”, 81100 Caserta, Italy
2
Department of Social Sciences, University of Foggia, 71121 Foggia, Italy
3
Department of Architecture and Industrial Design, University of Campania “L. Vanvitelli”, 81031 Aversa, Italy
*
Author to whom correspondence should be addressed.
Buildings 2025, 15(19), 3466; https://doi.org/10.3390/buildings15193466
Submission received: 4 August 2025 / Revised: 11 September 2025 / Accepted: 22 September 2025 / Published: 25 September 2025
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
Browse Figures
Versions Notes

Abstract

In the study of person-environment interaction, a well-established research field provided evidence on the power of natural environments and natural built spaces to improve human well-being. However, urban life or certain health conditions may make access to natural environments more difficult. This begs the question: is it possible to replicate the positive effects of green environments in interior spaces? To answer the question, here we manipulated the acoustic and visual features of five rooms to have nature-inspired indoor environments and urban-like indoor environments. To test the effect of these environmental features on people’s well-being two measures were taken into account: participants’ emotional state and participants’ physiological states (i.e., electrodermal activity levels). The results showed that nature-inspired rooms evoked more positive emotional states and led to decreased levels of electrodermal activity (i.e., relaxation) in participants. The findings align with so-called biophilia interior design, a practical perspective focused on the importance of bringing nature (e.g., colours and materiality) into built environments for optimising people’s health and well-being.

1. Introduction

Evidence from environmental psychology, neuroscience, and architecture indicates that the environment can elicit emotions and behavioural and physiological responses that affect people’s well-being [1,2,3,4,5,6]. Thus, one of the most complex challenges for architects and urban planners working together with psychologists is to design environments that consider diverse, often interconnected, human needs. In this respect, it becomes essential not only to include users’ emotions and feelings in the design process of spaces but also to know which aspects of the environment affect the way people interact with, experience, and feel within it [7,8,9]. Therefore, environmental psychologists face the complex challenge of getting a holistic understanding of the person–environment relationship, marked by dynamic and reciprocal processes [10,11].
In the study of person-environment interaction, a well-established research field provided strong evidence on the power of natural environments (e.g., forests, parks) to improve human physical and mental health and personal well-being [12,13,14]. For example, contact with nature fosters relaxation, renewal of cognitive resources, and reduction of fatigue and physiological stress indicators such as heart rate and skin conductance levels [15,16]. Research showed that even natural built spaces, i.e., urban parks or gardens, support individuals’ general well-being by enhancing positive mood, restoration, physical activities, and social contacts [3,5,17,18,19,20]. The propensity to seek healing environments through contact with nature belongs to our evolutionary heritage. In fact, human beings evolved in a natural rather than built environment while living in intimate contact with nature [21,22,23].
The biophilia hypothesis [23] explains the core of this human–nature bond, positing that individuals are genetically programmed to seek connection with all that is alive and vital. This is how, in challenging lifetimes, we find restoration and comfort in a walk among the trees, in the proximity of a stream, in the view of a park from the window.
Inspired by the biophilia hypothesis is the so-called biophilic design, an emerging discipline that attempts to promote individuals’ connection with built environments through the integration of natural or nature-analogous elements (e.g., colours, materials) [24]. In light of the evidence on the beneficial effect of nature on human well-being and considering that urban life or certain health conditions (e.g., hospitalised patients, deterioration due to ageing [25,26,27,28,29,30,31]) often limits access to nature, the present study took inspiration from the principles of biophilic design to explore how natural visual and acoustic elements can be integrated into interior spaces to improve individual well-being. Biophilic design is intended to design environments that are beneficial to human health and well-being using specific environmental properties that exploit the biological-based human propensity toward nature [32,33].
Furthermore, the study was premised on two considerations: first, although several studies demonstrated that the visual quality of the built environment plays an important role in the process of environmental experience affecting people’s perceptions of, evaluations of, and behaviour in their surroundings, we know people experience and represent their space through different sources of information with the brain biologically set up to manage, integrate, and combine these sensory inputs [2,34,35,36,37,38,39]. Moreover, evidence from environmental psychology supports the multisensory nature of human perception with studies showing, for example, how different combinations of audio–visual stimuli affect the evaluation of spaces in terms of pleasantness or safety [40,41,42]. Thus, here a multisensory approach was used to investigate the impact of indoor features on individuals’ responses to the environment. Specifically, we considered the visual and acoustic features as the two main streams of users’ environmental experience [26]. Secondly, to ensure a realistic perception of the environment, we implemented indoor scenarios via immersive virtual reality (IVR). It is widely recognised that IVR technology allows psychological, physical, and behavioural responses similar to those that would occur in real contexts [43,44,45] while keeping experimental control over the simulation [46].
Thus, in order to investigate whether and to what extent it is possible to replicate the benefits of green spaces in indoor environments, architects from the Department of Architecture and Industrial Design of the University of Campania L. Vanvitelli (Aversa, Italy) designed three rooms with natural-like colours and materials and two rooms with colours and materials reminiscent of urban environments. For acoustic features, we considered natural sounds vs. urban sounds.
To test the effect of environmental features on people’s well-being two measures were taken into account: individuals’ emotional state (explicit measure) and individuals’ physiological states (implicit measure).
For the emotional state, participants evaluated how each room made them feel (e.g., calm/nervous; happy/sad; see [47,48]); for the physiological reactions, we considered participants’ electrodermal activity (EDA) as a measure of the continuous variations in the electrical characteristics of the skin due to stimulation [49,50]. As several studies have shown that the induction of positive emotions results in decreased levels of EDA and feelings of well-being (e.g., recovery from stress) [15,16,51,52,53], here the EDA was used as a valid parameter for participants’ relaxation and general arousal to the different indoor environments.
We put forward the following hypotheses:
(1)
In line with the literature, we expect rooms with close-to-nature characteristics to be evaluated more positively and induce lower levels of EDA (i.e., relaxation) compared to rooms with more urban characteristics.
(2)
Considering the role of sounds in environmental evaluation, we expect rooms to be evaluated more positively when accompanied by natural sounds, especially for environments evocative of urban settings.
(3)
Finally, we hypothesise that natural sounds lead to a decrease in EDA levels (e.g., [15]).

2. Materials and Methods

  • Participants
Sample size was determined with a priori power analysis using G*Power 3.1.9.7 [54]. We specified a repeated-measures ANOVA (within-subject factors), with one group, five repeated measures, α = 0.05, and a desired power (1 – β) = 0.95. In the absence of prior empirical estimates with similar scenarios and procedures, we followed Cohen’s (2013) guidelines [55] and assumed a medium effect size (f = 0.25). The analysis indicated a required total sample size of 31 participants. For this study, 33 participants (23 F) aged 18–27 (M = 20.79; SD = 1.92) were recruited.
A sensitivity analysis was also conducted to determine the minimum effect size reliably detectable with the available sample [54,56]. With N = 33, α = 0.05, and 1 – β = 0.95, the design was sensitive to effects of at least f = 0.24 (ηp2 ≈ 0.055). All effects observed in the present study (ηp2 ranging from 0.14 to 0.36) exceeded this threshold.
Participants had normal or corrected to normal vision and normal colour vision and hearing; no one reported neurological problems or were being treated for psychiatric conditions. Furthermore, none of the participants was under the influence of drugs, alcohol, or caffeine at the time of the experimental session. All participants gave written informed consent to participate and were naive to the aim of the study. The study complied with the requirements of the local Ethics Committee of the Department of Psychology of the University of Campania “Luigi Vanvitelli” and the 2013 Helsinki Declaration [57].
  • Immersive virtual reality equipment
The IVR equipment was set up in a 5 × 4 × 3 m room of the Laboratory of Cognitive Science and Immersive Virtual Reality (CS-IVR, Dept. Psychology). The equipment included a PC workstation, Unreal Engine software (Epic Games, Inc; Cary, NC, USA) to present multisensory scenarios and the questionnaire, and an Oculus Rift S head-mounted display (single fast-switch LCD panel with a resolution of 2560 × 1440; 80 Hz refresh rate; field of view 115°) supplied with two Oculus Touch controllers.
Moreover, Sennheiser/HD600 (Sennheiser Electronic GmbH & Co. KG, Wedemark, Germany) headphones were included.
  • Visual Stimuli
Five different bedrooms were designed and reconstructed in virtual reality.
To avoid methodological confounders, we kept some features under control: the size of the room; the type and number of elements/objects; and the spatial layout of elements. Specifically, each room had a surface area of 9 m2, which was furnished with a bed, a table with a chair, an armchair, a wardrobe, and a window. Moreover, all rooms had the same arrangement: the bed on the right side of the room; the table with the chair and the wardrobe on the left side of the room; and the armchair in front of the window. Finally, all rooms were viewed from the same perspective (i.e., the window with the armchairs in front of the subject). Keeping these features stable, the rooms differed in colours, materials, and textures (for previous studies using a similar approach, see [4,58]). The criteria for classifying the rooms followed a design hierarchy intended to progressively shift from environments with neutral, predominantly monochromatic interiors and industrial materials to biophilic environments with interiors featuring colours and materials inspired by nature. This hierarchy should reflect a growing potential for promoting comfort and well-being for individuals [59,60]. Therefore, based on previous literature [59,60], we categorised the rooms as follows:
(1) Basic room: urban-like environment with prevalence of white and brownish colours, flat and neutral surfaces, a basic furniture style and covering materials (i.e., plastic and metal); (2) Modern room: white environment reminiscent of modern urban settings with prevalence of cold greyish colours (e.g., table and chair) and a linear essential furniture style with good-quality leather materials; (3) Comfort room: nature-like environment coloured in different shades of green and light blue with a modern furniture style, velvet-textured coverings and rounded furnishings; (4) Comfort-nature room: nature-like environment coloured in yellow and green with a modern furniture style and velvet-textured coverings; (5) Nature room: nature-like room coloured in dark green with a modern furniture style and wooden covering materials (see Figure 1).
  • Acoustic Stimuli
Based on previous studies (see [4,48]), here two different sound recordings reproducing a natural background sound environment, with birdsong, and an urban sound environment, with road traffic noise, were selected. Both recordings were filtered to simulate background sounds transmitted through the window inside the room. The soundtracks, reproduced by a laptop and a pair of Sennheiser headphones, were calibrated in the test room of the SENS i-Lab, at the Department of Architecture and Industrial Design, to reproduce an A-weighted sound equivalent level of 45 dB(A) in the listening position. The calibration was carried out by using an HSU III.2 artificial head coupled with a SQobold 4-channel system (Head Acoustics, Herzogenrath, Germany).
  • Multisensory scenarios
The five scenarios were combined with the two background natural and urban sounds in such a way as to obtain multisensory rooms with nature-like and urban-like interior features matched with birdsong in the background and multisensory rooms with nature-like and urban-like interior features matched with traffic noise in the background, for a total of ten multisensory scenarios.
  • Subjective emotional/mood state questionnaire
The 6-item questionnaire derives from a 12-item questionnaire developed by Masullo et al. [48]. The questionnaire is based on adjectives commonly used in studies assessing the emotional impact of environments on people [61,62,63,64,65]. Specifically, the questionnaire, using a 9-point Likert scale (1 = not at all; 9 = extremely), measures how calm, happy, energetic, sad, nervous, and weak each scenario made the participants feel.
  • EDA recording and data treatment
EDA signals were recorded using the EquivitalTM monitoring system equipped with the Sensor Electronics Module (SEM), an ancillary device for acquiring participants’ electrodermal activity in real time and supporting belts. An accompanying biofeedback software application, LabChart8 (ADInstruments Pty Ltd; Bella Vista, New South Wales, Australia), allowed the sampling and storage of physiological data. EDA signals were acquired using Ag/AgCl pre-gelled electrodes placed on the palmar surface of the index and middle fingers of the non-dominant hand. The real-time variation in conductance is calculated. All psychophysiological data were digitalised and stored at a frequency of 16 Hz.
Data treatment. The EDA signal consists of two main pieces of information—the signal level (or EDA tonic level—EDL) and signal dynamic response (or phasic EDA level—EDR) [66]. The tonic component of EDA indicates slow changes in the physiological arousal of individuals that follow the ongoing stimulation (e.g., long-lasting cognitive tasks, reading a text). The phasic component indicates changes in EDA that follow sudden and unexpected short events (e.g., a sudden sound, occurrence of a disturbing image). In this case, EDA shows sharp peaks (i.e., phasic responses) after the specific stimulus presentation (peak rise time window 1–5 s) [51,66].
In this study, the environmental exposure undergone by the participants is low-arousing and not event-related, meaning that the stimulation elicits minimal physiological and emotional activation typical of monotonous and prolonged experiences in the absence of unexpected or disturbing events responsible for specific arousal responses (i.e., EDA peaks induced by a specific event). Based on this, here we focused on EDA reactivity as the changes in EDA levels from its baseline level [66] without decomposing the physiological signal into its tonic and phasic components. Therefore, considering the time window of 45 s (time for the participant to become familiar with the environment), we calculated the percentage variation (delta%) of EDA levels during stimulation (i.e., during exposure to the multisensory scenario) from baseline (participant’s initial rest period; 5 min). We computed the percentage variation as follows:
Δ % = X f − X i X i   ×   100
where Xf = mean EDA reactivity during the environmental exposure (final value); Xi = mean EDA at baseline (initial value). EDA values are expressed in microsiemens (μS).
  • Procedure
After giving their written consent, participants were introduced to the experimental room and presented with physiological signals recording equipment, immersive virtual reality devices, and task instructions. The experimenters showed the HMD, the EquivitalTM recording system, and how to use the controller. Before placing the belt with the SEM and the electrodes for EDA signal acquisition, the experimenters ensured that the participant’s skin was dry. To prevent discomfort, a female experimenter helped women with the belt and EDA electrodes, and a male experimenter helped men with the same equipment. After that, the participant was invited to sit in a comfortable chair.
At this point, the experimenters set up the physiological signal recording equipment for the adaptation phase and the registration of EDA levels at baseline: participants were told to be at rest (even with their eyes closed if they preferred) and not to move. To facilitate relaxation, participants wore noise-reducing headphones. Only once EDA levels remained constant without fluctuations did the experimenters begin to acquire the participant’s baseline for five minutes.
After that, the experimental session began: the participant wore the HMD and headphones, held the controller in his/her dominant hand (to answer the evaluation questionnaire), and was immersed within the multisensory scenario. The participant was told to freely explore the scenario (exploration phase = 45 s) by moving the head (avoiding any sudden movements with the body and limbs) until a green dot indicated the occurrence of the evaluation questionnaire. Then, the participant was asked to rate (on a scale from 1 = not at all to 9 = very much) how calm, energetic, happy, nervous, weak, and sad the room made him/her feel (evaluation phase = free time). After a 30 s timelapse, another scenario was presented. The experimental session comprised two blocks: the block with the five rooms featuring nature-like interior characteristics and the block with the five rooms featuring urban-like interior characteristics. The order of the blocks was counterbalanced across participants. Moreover, within each block, the order of presentation for rooms with natural sounds and rooms with urban sounds was also counterbalanced. Namely, half of the participants were presented with the nature-like rooms first and then with the urban-like rooms (and of these, half explored the rooms with the birdsong first and then the rooms with the traffic noise), with the opposite for the other half. The EDA levels were recorded for the entire duration of the experimental session. In order to avoid an overlapping effect of physiological signals and thus of electrodermal reactivity across the different scenarios, the following precautions were taken [50,67]: a 5 min break between the two experimental blocks; a 3 min break between each sound condition (natural vs. urban sounds); 30 s inter-stimulus interval (ISI) between the presentation of each scenario after the evaluation questionnaire [50]. Thus, ensuring a sufficient temporal distance between the different stimulations (i.e., the presentation of each scenario) allows for the subject’s electrodermal recovery. The entire experimental session lasted about 45 min.
  • Data Analysis
First, we explored the effect of nature-like and urban-like interior features of the environments on participants’ subjective evaluations and EDA levels. Therefore, the following analyses were planned:
(1)
Two separate one-way ANOVAs on the mean of the three positive adjectives (calm, energetic, happy; positive dimension) and on the mean of the three negative adjectives (nervous, weak, sad; negative dimension) with Rooms (five levels: Basic, Modern, Comfort, Nature, Comfort-nature) as a factor.
(2)
A one-way ANOVA on the percentage variation of EDA levels from its baseline (Δ%) with Rooms (five levels: Basic, Modern, Comfort, Nature, Comfort-nature) as a factor. Then, to further explore the effect of sounds on participants’ subjective evaluations and EDA levels, we planned the following analyses distinguishing the rooms accompanied by natural sounds from those accompanied by urban sounds.
(3)
Four one-way ANOVAs on the mean of the three positive adjectives (calm, energetic, happy; positive dimension) and on the mean of the three negative adjectives (nervous, weak, sad; negative dimension) with Rooms (five levels: Basic, Modern, Comfort, Nature, Comfort-nature) as a factor were performed considering the multisensory scenarios with natural sounds and urban sounds separately.
(4)
Two one-way ANOVAs on the percentage variation of EDA level from its baseline (Δ%) with Rooms (five levels: Basic, Modern, Comfort, Nature, Comfort-nature) as factor were performed considering the multisensory scenarios with natural sounds and urban sounds separately.
Therefore, the positive and negative dimensions of the subjective evaluation measure the overall impact (positive vs. negative) of each scenario on individuals.
Positive values of Δ% indicate an increase in EDA reactivity and negative values indicate a decrease in EDA reactivity with respect to the initial EDA levels.
Finally, the Newman-Keuls post-hoc test was used, and the magnitude of significant effects was expressed by partial eta-squared (ηp2). Data points outside ≥ 2.5 SD were discarded (2.3% of all data).

3. Results

  • Effect of nature-like and urban-like interior features on subjective evaluations of environments
Positive Dimension. The effect of the factor Rooms emerged (F (4, 128) = 15.53, p < 0.00001, ηp2 = 0.33). The post-hoc comparisons showed that the Comfort-nature room was evaluated more positively than all other rooms (at least, p < 0.05), and the opposite was observed for the Basic room (at least, p < 0.01). No other significant differences emerged. The related means were: Comfort-nature room = 6.15, SD = 1.25; Comfort room = 5.34, SD = 1.08; Nature room = 5.47, SD = 1.43; Modern room = 5.03, SD = 0.89; Basic room = 4.23, SD = 1.45.
Negative Dimension. The effect of the factor Rooms emerged (F (4, 128) = 15.21, p < 0.00001, ηp2 = 0.32). The post-hoc comparisons showed that the Basic and Modern rooms were evaluated more negatively than all other rooms (at least, p < 0.05). The Comfort and Nature rooms were evaluated more negatively than the Comfort-nature room (at least, p < 0.05). No other significant differences emerged. The related means were: Comfort-nature room = 2.12, SD = 1.00; Comfort room = 2.88, SD = 1.29; Nature room = 2.67, SD = 1.26; Modern room = 3.38, SD = 1.18; Basic room = 3.88, SD = 1.57.
The results are shown in Figure 2.
  • Effect of nature-like and urban-like interior features of environments on EDA levels
The effect of the factor Rooms emerged (F (4, 128) = 11.52, p < 0.00001, ηp2 = 0.26). The post-hoc comparisons showed that the three rooms with nature-like interior features induced a reduction in EDA levels compared to the rooms with urban-like interior features (at least, p < 0.001). No other significant differences emerged. The related means were: Comfort-nature room = −12.51, SD = 19.17; Comfort room = −13.91, SD = 16.41; Nature room = −15.66, SD = 21.97; Modern room = 5.95, SD = 20.64; Basic room = 4.65, SD = 24.76 (Figure 3).
  • Effect of sounds on subjective evaluations of environments
Positive Dimension: rooms with natural sounds. The effect of the factor Rooms emerged (F (4, 128) = 7.35, p < 0.0001, ηp2 = 0.19). The effect was due to the Basic room being evaluated less positively than all others (at least, p < 0.01). The related means were: Basic = 5.10, SD = 1.80; Modern = 6.17, SD = 1.33; Comfort = 5.95, SD = 1.30; Nature = 6.03, SD = 1.53; Comfort-nature = 6.60, SD = 1.55.
Positive Dimension: rooms with urban sounds. The effect of the factor Rooms emerged (F (4, 128) = 18.15, p < 0.00001, ηp2 = 0.36). The post-hoc test showed that the Comfort-nature room was rated more positively than all others (at least, p < 0.01), while the Comfort and Nature rooms were rated more positively than the Basic and Modern rooms (at least, p < 0.01). No difference emerged between the Comfort and Nature rooms (p > 0.05) and between the Basic and Modern rooms (p > 0.05). The related means were: Basic = 3.41, SD = 1.52; Modern = 3.89, SD = 1.28; Comfort = 4.72, SD = 1.30; Nature = 4.92, SD = 1.66; Comfort-nature = 5.71, SD = 1.43.
The results are shown in Figure 4.
Negative Dimension: rooms with natural sounds. The effect of the factor Rooms emerged (F (4, 128) = 8.34, p < 0.0001, ηp2 = 0.21). The post-hoc test showed that the Basic room was rated more negatively than all others (at least, p < 0.05). The Modern room was rated more negatively than the Comfort-nature room (p < 0.05). The related means were: Basic = 3.34, SD = 1.83; Modern = 2.64, SD = 1.58; Comfort = 2.45, SD = 1.54; Nature = 2.18, SD = 1.27; Comfort-nature = 1.90, SD = 0.99.
Negative Dimension: rooms with urban sounds. The effect of the factor Rooms emerged (F (4, 128) = 12.43, p < 0.00001, ηp2 = 0.28). The post-hoc test showed that the Basic and Modern rooms were evaluated more negatively than all others (at least, p < 0.05). Moreover, the Comfort and Nature rooms were evaluated more negatively than the Comfort-nature room (at least, p < 0.05). No difference emerged between the Comfort and Nature rooms (p > 0.05) and between the Basic and Modern rooms (p > 0.05). The related means were: Basic = 4.48, SD = 1.95; Modern = 4.13, SD = 1.60; Comfort = 3.31, SD = 1.48; Nature = 3.16, SD = 1.55; Comfort-nature = 2.37, SD = 1.38.
The results are shown in Figure 5.
  • EDA levels
Rooms with natural sounds. The effect of the factor Rooms emerged (F (4, 128) = 5.10, p < 0.01, ηp2 = 0.14). The post-hoc test showed that Nature and Comfort-nature rooms induced a reduction in EDA levels compared to the Modern and Basic rooms (at least, p < 0.05). The Comfort room induced a reduction in EDA levels compared to the Modern room (at least, p < 0.01). The comparison Comfort room vs. Basic room did not reach significance but showed the same tendency (p = 0.059). Finally, no difference emerged between the three rooms with nature-like interior features (ps > 0.05) and between the Basic and Modern rooms (p < 0.05). The related means were: Basic = 2.85, SD = 26.10; Modern = 6.43, SD = 22.76; Comfort = −9.27, SD = 22.81; Nature = −13.18, SD = 25.32; Comfort-nature = −9.08, SD = 20.58.
Rooms with urban sounds. The effect of the factor Rooms emerged (F (4, 128) = 10.85, p < 0.000001, ηp2 = 0.25). The post-hoc test showed that the three rooms with nature-like interior features and urban sounds induced a reduction in EDA levels compared to the rooms with urban-like interior features and sounds (at least, p < 0.001). No other significant differences emerged. The related means were: Basic = 8.27, SD = 34.73; Modern = 5.47, SD = 22.34; Comfort = −18.54, SD = 22.52; Nature = −18.15, SD = 24.06; Comfort-nature = −15.94, SD = 24.83.
The results are shown in Figure 6.

4. Discussion

The study aimed at investigating if it would be possible to replicate the benefits of green spaces on human emotional and psychophysiological reactions in indoor environments. To this end, five bedrooms were designed with close-to-nature or close-to-urban visual characteristics. In addition, each scenario was combined with a natural sound (birdsong) and an urban sound (traffic). Hence, we measured the impact of these multisensory scenarios on individual emotional and psychophysiological reactions.
As for individuals’ emotional state, results showed that the three rooms with visual nature-like features had a more positive impact on individuals’ emotions compared to the rooms with urban-like features. Furthermore, among the nature-like rooms, the Comfort-nature room (i.e., the indoor environment coloured in green and yellow and furnished with soft-touch materials) induced a more positive emotional state than the Nature (i.e., the indoor environment coloured in green, furnished with soft-touch materials and wooden covering materials) and Comfort (i.e., the indoor environment coloured in green and blue, furnished with soft-touch materials) ones. Coherently, the Basic (i.e., the environment featured with white/brownish colours and furnished with plastic and metal covering materials) and Modern (i.e., total white environment furnished with high-quality leather materials) rooms had a negative impact on individuals’ emotional state.
More interestingly, considering the psychophysiological side, the exposure to rooms designed with features resembling nature led to a calming effect by decreasing EDA levels compared to the exposure to rooms with urban characteristics. The fact that psychophysiological data showed no significant differences in electrodermal activity (EDA) among the three nature-inspired rooms, all of which were associated with lower arousal levels compared to the urban condition, suggests that it is not the specific choice of natural colours or materials that matters most but rather the evocation of nature itself, which serves as a cross-sensory cue that supports relaxation and psychological restoration.
Exploring the contribution of sounds to people’s emotional and psychophysiological reactions, the current results showed that natural sounds improved the impact of the Modern urban-like environment but not the Basic one on participants’ emotional reactions. On the other hand, when combined with the traffic sound, the Basic and Modern rooms had a negative impact on participants’ emotions compared to all others. In addition, the sound of traffic worsened the evaluations of the Comfort and Nature rooms but not those of the Comfort-nature room. Therefore, with respect to subjective emotional reactions to indoor environments, a natural sound is able to improve the evaluation of an indoor environment whose visual features are reminiscent of a modern urban environment; on the other hand, indoor features reminiscent of natural elements (in shades of yellow and green) are able to counteract the negative effect of urban sounds (e.g., traffic).
On the psychophysiological side, the results showed that, when combined with natural sounds, the Nature and Comfort-nature rooms decreased EDA levels compared to the Modern and Basic rooms, while the Comfort room decreased EDA levels compared to the Modern room. When combined with urban sounds, the three nature-like rooms decreased EDA levels compared to the two urban-like rooms. Therefore, with respect to psychophysiological responses, natural sounds did not improve the impact of urban-like settings on participants’ physiological activation levels (i.e., the exposure to birdsong in urban-like environments did not lead to a calming effect); similarly, urban sounds did not worsen the de-activating effect of nature-like settings (i.e., the exposure to the traffic sound in nature-like environments did not cause an increase in EDA levels).
Considering all the above, some considerations can be drawn. First, these results are consistent with studies showing the positive effect of nature and its relationship with people’s mood (e.g., [14,25,68,69,70]). As with outdoor environments, people also seek out and benefit from elements reminiscent of nature in indoor environments (e.g., [3,4,22]). This demonstrates that indirect connections with nature can also occur in the built environment: in its colours (e.g., green, yellow) and acoustic aspects (e.g., birdsong), people find their emotional and physical well-being [3,4,71]. In this vein, the study would indicate that designing nature-based environments can contrast the negative outcomes of urban life by fostering the recovery from individuals’ physiological reactions to stress through a calming effect expressed, for example, in decreased EDA levels [22,72,73]. These results corroborate previous research showing EDA to be a reliable physiological marker for stress assessment and recovery. Several studies have demonstrated significant EDA reductions after exposure to restorative stimuli, including natural scenes [74], musical interventions [75], and mindfulness-based practices [76,77]. These findings support the interpretation that biophilic design elements may act as restorative cues, facilitating autonomic downregulation similar to more traditional stress-reduction techniques.
To sum up, the present work suggests that it is possible to replicate the benefits of green/natural spaces in indoor environments. This evidence suits the biophilia hypothesis by showing that people are naturally drawn to elements reminiscent of nature, even in indoor environments [21,23], as evidenced by reduced electrodermal activity (EDA) in rooms that emulate natural contexts compared to those emulating urban contexts. Our skin functions as the primary interface between the body and the environment, so exposure to nature-inspired contexts appears to trigger an innate, genetically programmed response to the environment in which we evolved, producing calming and positive effects [78].

5. Conclusions

The present findings align with so-called biophilia interior design, a practical perspective focused on the importance of bringing nature (e.g., colours, lights, and materiality) into built environments for optimising people’s health and well-being [22,71,79]. This study provides empirical support for the calming effects of nature-inspired indoor environments. Participants exposed to rooms designed with natural visual and acoustic features showed significantly lower electrodermal activity levels compared to those in urban-styled rooms, confirming a measurable reduction in physiological arousal. These findings align with biophilic design principles and reinforce the relevance of multisensory environmental features in fostering stress recovery.
From an applied perspective, biophilic strategies may differ across healthcare settings. In acute medical environments, where cleanliness and sterility are paramount, indirect interventions such as restorative soundscapes, natural colour palettes, and daylight exposure are most appropriate [80]. In contrast, long-term care centers and elderly communities may benefit from direct integrations of nature, including plants, indoor gardens, or accessible green spaces, which also support physical activity and social interaction [81].
Ultimately, reconnecting individuals with nature through thoughtful design may offer a low-cost, high-impact strategy to improve quality of life and reduce stress, while encouraging interdisciplinary collaboration between healthcare professionals, designers, and environmental psychologists.

6. Limitations

Some limitations should be acknowledged. First, the sample included only young adults, which limits the generalisability of findings to other populations, such as the elderly, who are among the most relevant targets for biophilic interventions [5].
A growing literature, summarised in a recent review highlighting the “healing power of nature” in healthcare contexts [81], supports extension of our findings to these groups. Empirical studies with older adults show that immersive virtual nature can improve affect and reduce stress [82], enhance vigor and connectedness among nursing-home residents [83], and promote restorative emotional experiences in community-dwelling seniors [84]. Benefits have also been demonstrated in more fragile populations: naturalistic VR scenarios have been shown to be feasible and effective in eliciting relaxation among patients with cognitive impairment [85], and tailored VR nature meditation programmes reduced stress and negative affect in older adults in a recent randomised controlled trial [86]. Further, mood and cognitive engagement improvements have been reported in pilot work with older participants using nature-based VR [87]. However, nevertheless, future studies are needed to clarify whether age-related differences affect physiological responses (e.g., in terms of EDA reactivity) to nature-inspired indoor environments.
Second, the exposure time to each room was brief (45 s), which may capture only short-term physiological effects. While a calming effect on EDA was observed, it remains unclear whether this effect would persist or evolve with longer or repeated exposure. Future research should include longitudinal or recovery-based paradigms, such as exposing participants to stressors followed by prolonged stays in different environments, to assess the durability of the effect.
Lastly, our experiment does not allow us to verify whether some features, such as colour schemes, material choices, or their combination, carry more weight in eliciting stress-reducing responses. A more granular experimental design could isolate and test the impact of individual biophilic components across sensory modalities.

Author Contributions

Conceptualisation, T.I. and M.M.; methodology, T.I., M.R. and F.R.; software, F.C. (Federico Cioffi), M.R., L.C. and F.C. (Fabiola Capitelli); resources, F.C. (Federico Cioffi), M.R., L.C. and F.C. (Fabiola Capitelli); formal analysis, F.R., M.R. and T.I.; investigation, M.R., L.C. and F.C. (Fabiola Capitelli); data curation, M.R., F.R. and L.C.; visualisation, M.R. and L.C.; writing—original draft preparation, M.R.; writing—review and editing, M.R., F.R., G.R., M.M. and T.I.; project administration, T.I., M.M. and L.M.; supervision, T.I. and M.M.; funding acquisition, T.I., M.M., L.M., M.R., G.R. and F.R. All authors have read and agreed to the published version of the manuscript.

Funding

Research activities were funded by the Ministry of University and Research, through the Industrial research project PON Ricerca e Innovazione 2014—2020, ARS01_00307, Brain Virtual Interactivity Platform (BraVI). The APC was partially funded by Project ENACTEN “Age-friendly Environments: meeting the cognitive and emotional needs of the elderly in their daily life” (CUP: B63C23000650005) under the funding of fundamental and applied research projects dedicated to young researchers—Università degli Studi della Campania “Luigi Vanvitelli”.

Data Availability Statement

The data are available on request from the authors.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Galvez-Pol, A.; Nadal, M.; Kilner, J.M. Emotional representations of space vary as a function of peoples’ affect and interoceptive sensibility. Sci. Rep. 2021, 11, 16150. [Google Scholar] [CrossRef] [PubMed]
  2. Jiang, B.; Xu, W.; Ji, W.; Kim, G.; Pryor, M.; Sullivan, W.C. Impacts of nature and built acoustic-visual environments on human’s multidimensional mood states: A cross-continent experiment. J. Environ. Psychol. 2021, 77, 101659. [Google Scholar] [CrossRef]
  3. Rapuano, M.; Ruotolo, F.; Ruggiero, G.; Masullo, M.; Maffei, L.; Galderisi, A.; Palmieri, A.; Iachini, T. Spaces for relaxing, spaces for recharging: How parks affect people’s emotions. J. Environ. Psychol. 2022, 81, 101809. [Google Scholar] [CrossRef]
  4. Rapuano, M.; Sarno, M.; Ruotolo, F.; Ruggiero, G.; Iuliano, S.; Masullo, M.; Maffei, L.; Cioffi, F.; Iachini, T. Emotional reactions to different indoor solutions: The role of age. Buildings 2023, 13, 1737. [Google Scholar] [CrossRef]
  5. Ruotolo, F.; Rapuano, M.; Masullo, M.; Maffei, L.; Ruggiero, G.; Iachini, T. Well-being and multisensory urban parks at different ages: The role of interoception and audiovisual perception. J. Environ. Psychol. 2024, 93, 102219. [Google Scholar] [CrossRef]
  6. Zhang, J.W.; Howell, R.T.; Iyer, R. Engagement with natural beauty moderates the positive relation between connectedness with nature and psychological well-being. J. Environ. Psychol. 2014, 38, 55–63. [Google Scholar] [CrossRef]
  7. Ellard, C. Neuroscience, wellbeing, and urban design: Our universal attraction to vitality. Psychol. Res. Urban Soc. 2020, 3. [Google Scholar] [CrossRef]
  8. Mowen, A.J.; Hickerson, B.D.; Kaczynski, A.T. Beyond the Ribbon Cutting: Evaluating the Behavioral and Experiential Impacts of a Neighborhood Park Renovation. J. Park Recreat. Adm. 2013, 31, 57–77. [Google Scholar]
  9. Spence, C. Senses of place: Architectural design for the multisensory mind. Cogn. Res. Princ. Implic. 2020, 5, 46. [Google Scholar] [CrossRef] [PubMed]
  10. Kupfer, J.A. Theory in landscape ecology and its relevance to biogeography. In Handbook of Biogeography; SAGE: London, UK, 2011; pp. 57–74. [Google Scholar]
  11. Uzzell, D.; Romice, O. Analysing Environmental Experiences1. In Espaces de vie: Aspects de la Relation Homme-Environnement; Moser, G., Weiss, K., Eds.; Armand Colin: Paris, France, 2003; pp. 49–83. [Google Scholar]
  12. Nilsson, K.; Sangster, M.; Konijnendijk, C.C. Forests, trees and human health and well-being: Introduction. In Forests, Trees and Human Health; Springer: Dordrecht, The Netherlands, 2010; pp. 1–19. [Google Scholar]
  13. Van den Berg, M.; Van Poppel, M.; Van Kamp, I.; Andrusaityte, S.; Balseviciene, B.; Cirach, M.; Danileviciute, A.; Ellis, N.; Hurst, G.; Masterson, D.; et al. Visiting green space is associated with mental health and vitality: A cross-sectional study in four european cities. Health Place 2016, 38, 8–15. [Google Scholar] [CrossRef]
  14. Zhang, J.; Yu, Z.; Zhao, B.; Sun, R.; Vejre, H. Links between green space and public health: A bibliometric review of global research trends and future prospects from 1901 to 2019. Environ. Res. Lett. 2020, 15, 063001. [Google Scholar] [CrossRef]
  15. Alvarsson, J.J.; Wiens, S.; Nilsson, M.E. Stress recovery during exposure to nature sound and environmental noise. Int. J. Environ. Res. Public Health 2010, 7, 1036–1046. [Google Scholar] [CrossRef]
  16. Knaust, T.; Felnhofer, A.; Kothgassner, O.D.; Höllmer, H.; Gorzka, R.J.; Schulz, H. Exposure to virtual nature: The impact of different immersion levels on skin conductance level, heart rate, and perceived relaxation. Virtual Real. 2022, 26, 925–938. [Google Scholar] [CrossRef]
  17. Rapuano, M.; Ruotolo, F.; Ruggiero, G.; Cannito, L.; Capitelli, F.; Cioffi, F.; Masullo, M.; Maffei, L.; Iachini, T. Affective Evaluations of Rooms in Immersive Virtual Reality: The Effect of Naturalistic Elements. In Proceedings of the 2023 IEEE International Conference on Metrology for eXtended Reality, Artificial Intelligence and Neural Engineering (MetroXRAINE), Milano, Italy, 25–27 October 2023; pp. 933–938. [Google Scholar]
  18. Roe, J.J.; Aspinall, P.A.; Ward Thompson, C. Coping with stress in deprived urban neighborhoods: What is the role of green space according to life stage? Front. Psychol. 2017, 8, 1760. [Google Scholar] [CrossRef]
  19. Ward Thompson, C.; Aspinall, P.A. Natural environments and their impact on activity, health, and quality of life. Appl. Psychol. Health Well-Being 2011, 3, 230–260. [Google Scholar] [CrossRef]
  20. Ward Thompson, C. Landscape and Health special issue. Landsc. Res. 2016, 41, 591–597. [Google Scholar] [CrossRef]
  21. Kellert, S.; Wilson, E.O. The Biophilia Hypothesis; Island Press: Washington, DC, USA, 1993. [Google Scholar]
  22. Kellert, S.R. Biodiversity, quality of life, and evolutionary psychology. In Biodiversity Change and Human Health: From Ecosystem Services to Spread of Disease; Sala, O.E., Meyerson, L.A., Parmesan, C., Eds.; Island Press: Washington, DC, USA, 2009; pp. 98–128. [Google Scholar]
  23. Wilson, E.O. Biophilia; Harvard University Press: Cambridge, UK, 1984. [Google Scholar]
  24. Gaekwad, J.S.; Sal Moslehian, A.; Roös, P.B.; Walker, A. A meta-analysis of emotional evidence for the biophilia hypothesis and implications for biophilic design. Front. Psychol. 2022, 13, 750245. [Google Scholar] [CrossRef]
  25. Ekkel, E.D.; de Vries, S. Nearby green space and human health: Evaluating accessibility metrics. Landsc. Urban Plan. 2017, 157, 214–220. [Google Scholar] [CrossRef]
  26. Depledge, M.H.; Stone, R.J.; Bird, W.J. Can natural and virtual environments be used to promote improved human health and wellbeing? Environ. Sci. Technol. 2011, 45, 4660–4665. [Google Scholar] [CrossRef]
  27. Kaplan, R. The nature of the view from home: Psychological benefits. Environ. Behav. 2001, 33, 507–542. [Google Scholar] [CrossRef]
  28. Schweitzer, M.; Gilpin, L.; Frampton, S. Healing spaces: Elements of environmental design that make an impact on health. J. Altern. Complement. Med. 2004, 10 (Suppl. S1), S-71. [Google Scholar] [CrossRef]
  29. Sang Å, O.; Knez, I.; Gunnarsson, B.; Hedblom, M. The effects of naturalness, gender, and age on how urban green space is perceived and used. Urban For. Urban Green. 2016, 18, 268–276. [Google Scholar] [CrossRef]
  30. Mostajeran, F.; Krzikawski, J.; Steinicke, F.; Kühn, S. Effects of exposure to immersive videos and photo slideshows of forest and urban environments. Sci. Rep. 2021, 11, 3994. [Google Scholar] [CrossRef] [PubMed]
  31. Orr, J.E.; Ayappa, I.; Eckert, D.J.; Feldman, J.L.; Jackson, C.L.; Javaheri, S.; Khayat, R.N.; Martin, J.L.; Mehra, R.; Naughton, M.Y.; et al. Research priorities for patients with heart failure and central sleep apnea. An official American Thoracic Society research statement. American J. Respir. Crit. Care Med. 2021, 203, e11–e24. [Google Scholar]
  32. Kaplan, S. The restorative benefits of nature: Toward an integrative framework. J. Environ. Psychol. 1995, 15, 169–182. [Google Scholar] [CrossRef]
  33. Scopelliti, M.; Carrus, G.; Bonaiuto, M. Is it really nature that restores people? A comparison with historical sites with high restorative potential. Front. Psychol. 2019, 9, 2742. [Google Scholar] [CrossRef]
  34. Calvert, G.; Spence, C.; Stein, B.E. (Eds.) The Handbook of Multisensory Processes; MIT Press: Cambridge, MA, USA, 2004. [Google Scholar]
  35. Ernst, M.O.; Bülthoff, H.H. Merging the senses into a robust percept. Trends Cogn. Sci. 2004, 8, 162–169. [Google Scholar] [CrossRef]
  36. Frassinetti, F.; Bolognini, N.; Làdavas, E. Enhancement of visual perception by crossmodal visuo-auditory interaction. Exp. Brain Res. 2002, 147, 332–343. [Google Scholar] [CrossRef]
  37. Watkins, S.; Shams, L.; Josephs, O.; Rees, G. Activity in human V1 follows multisensory perception. NeuroImage 2007, 37, 572–578. [Google Scholar] [CrossRef]
  38. Ruotolo, F.; Maffei, L.; Di Gabriele, M.; Iachini, T.; Masullo, M.; Ruggiero, G.; Senese, V.P. Immersive virtual reality and environmental noise assessment: An innovative audio–visual approach. Environ. Impact Assess. Rev. 2013, 41, 10–20. [Google Scholar] [CrossRef]
  39. Viollon, S.; Lavandier, C.; Drake, C. Influence of visual setting on sound ratings in an urban environment. Appl. Acoust. 2002, 63, 493–511. [Google Scholar] [CrossRef]
  40. Banks, S.J.; Ng, V.; Jones-Gotman, M. Does good+ good= better? A pilot study on the effect of combining hedonically valenced smells and images. Neurosci. Lett. 2012, 514, 71–76. [Google Scholar] [CrossRef]
  41. Bhattacharya, J.; Lindsen, J.P. Music for a brighter world: Brightness judgment bias by musical emotion. PLoS ONE 2016, 11, e0148959. [Google Scholar] [CrossRef]
  42. Masullo, M.; Maffei, L.; Pascale, A.; Senese, V.P.; De Stefano, S.; Chau, C.K. Effects of evocative audio-visual installations on the restorativeness in urban parks. Sustainability 2021, 13, 8328. [Google Scholar] [CrossRef]
  43. Iachini, T.; Coello, Y.; Frassinetti, F.; Senese, V.P.; Galante, F.; Ruggiero, G. Peripersonal and interpersonal space in virtual and real environments: Effects of gender and age. J. Environ. Psychol. 2016, 45, 154–164. [Google Scholar] [CrossRef]
  44. Riva, G.; Baños, R.M.; Botella, C.; Mantovani, F.; Gaggioli, A. Transforming experience: The potential of augmented reality and virtual reality for enhancing personal and clinical change. Front. Psychiatry 2016, 7, 164. [Google Scholar] [CrossRef]
  45. Slater, M.; Steed, A.; Chrysanthou, Y. Computer Graphics and Virtual Environments: From Realism to Real-Time; Pearson Education: London, UK, 2002. [Google Scholar]
  46. Parsons, T.D. Virtual reality for enhanced ecological validity and experimental control in the clinical, affective and social neurosciences. Front. Hum. Neurosci. 2015, 9, 660. [Google Scholar] [CrossRef] [PubMed]
  47. Masullo, M.; Maffei, L.; Cioffi, F.; Palmieri, A.; Galderisi, A.; Li, J.; Pascale, A.; Ianchini, T.; Ruggiero, G.; Ruotolo, F.; et al. Preliminary qualification of a small audio-visual dataset for a multisensory study on urban parks. In Proceedings of the INTER-NOISE and NOISE-CON Congress and Conference Proceedings, Online, 16–20 November 2020; Volume 261, pp. 2967–2977. [Google Scholar]
  48. Masullo, M.; Maffei, L.; Iachini, T.; Rapuano, M.; Cioffi, F.; Ruggiero, G.; Ruotolo, F. A questionnaire investigating the emotional salience of sounds. Appl. Acoust. 2021, 182, 108281. [Google Scholar] [CrossRef]
  49. Boucsein, W. Electrodermal Activity; Springer Science & Business Media: Basel, Switzerland, 2012. [Google Scholar]
  50. Braithwaite, J.J.; Watson, D.G.; Jones, R.; Rowe, M. A guide for analysing electrodermal activity (EDA) & skin conductance responses (SCRs) for psychological experiments. Psychophysiology 2013, 49, 1017–1034. [Google Scholar]
  51. Boucsein, W. Electrodermal Activity, 2nd ed.; Springer: New York, NY, USA, 2007. [Google Scholar]
  52. Kreibig, S.D. Autonomic nervous system activity in emotion: A review. Biol. Psychol. 2010, 84, 394–421. [Google Scholar] [CrossRef]
  53. Sandler, H.; Fendel, U.; Buße, P.; Rose, M.; Bösel, R.; Klapp, B.F. Relaxation–induced by vibroacoustic stimulation via a body monochord and via relaxation music–is associated with a decrease in tonic electrodermal activity and an increase of the salivary cortisol level in patients with psychosomatic disorders. PLoS ONE 2017, 12, e0170411. [Google Scholar] [CrossRef]
  54. Faul, F.; Erdfelder, E.; Lang, A.G.; Buchner, A. G* Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav. Res. Methods 2007, 39, 175–191. [Google Scholar] [CrossRef]
  55. Cohen, J. Statistical Power Analysis for the Behavioral Sciences; Routledge: London, UK, 2013. [Google Scholar]
  56. Perugini, M.; Gallucci, M.; Costantini, G. A practical primer to power analysis for simple experimental designs. Rev. Int. Psychol. Soc. 2018, 31, 1–23. [Google Scholar] [CrossRef]
  57. World Medical Association. World Medical Association Declaration of Helsinki: Ethical principles for medical research involving human subjects. JAMA 2013, 310, 2191–2194. [Google Scholar] [CrossRef]
  58. Maseda, A.; Sanchez, A.; Marante, M.P.; Gonzalez-Abraldes, I.; de Labra, C.; Millan-Calenti, J.C. Multisensory stimulation on mood, behavior, and biomedical parameters in people with dementia: Is it more effective than conventional one-toone stimulation? Am. J. Alzheimer’s Dis. Other Dement. 2014, 29, 637–647. [Google Scholar] [CrossRef] [PubMed]
  59. Enwin, A.D.; Ikiriko, T.D.; Jonathan-Ihua, G.O. The role of colours in interior design of liveable spaces. Eur. J. Theor. Appl. Sci. 2023, 1, 242–262. [Google Scholar] [CrossRef] [PubMed]
  60. Dazkir, S.S.; Read, M.A. Furniture forms and their influence on our emotional responses toward interior environments. Environ. Behav. 2012, 44, 722–732. [Google Scholar] [CrossRef]
  61. Gil, S.; Le Bigot, L. Seeing life through positive-tinted glasses: Color–meaning associations. PLoS ONE 2014, 9, e104291. [Google Scholar] [CrossRef]
  62. Mccormick, I.A.; Walkey, F.H.; Taylor, A.J.W. The stress arousal checklist: An independent analysis. Educ. Psychol. Meas. 1985, 45, 143–146. [Google Scholar] [CrossRef]
  63. McNair, D.M.; Lorr, M.; Droppleman, L.F. Profile of Mood States; Educational and Industrial Testing Service: San Diego, CA, USA, 1981. [Google Scholar]
  64. Osgood, C.E. The nature and measurement of meaning. Psychol. Bull. 1952, 49, 197–237. [Google Scholar] [CrossRef]
  65. Russell, J.A.; Lanius, U.F. Adaptation level and the affective appraisal of environments. J. Environ. Psychol. 1984, 4, 119–135. [Google Scholar] [CrossRef]
  66. Geršak, G. Electrodermal activity-a beginner’s guide. Electrotech. Rev./Elektrotehniski Vestn. 2020, 87, 175–182. [Google Scholar]
  67. Barry, R. Preliminary process theory: Towards an integrated account of the psychophysiology of cognitive processes. Acta Neurobiol. Exp. 1996, 56, 469–484. [Google Scholar] [CrossRef]
  68. Hartig, T. Restorative environments. Encycl. Appl. Psychol. 2004, 3, 273–279. [Google Scholar]
  69. Reyes-Riveros, R.; Altamirano, A.; De La Barrera, F.; Rozas, D.; Vieli, L.; Meli, P. Linking public urban green spaces and human well-being: A systematic review. Urban For. Urban Green. 2021, 61, 127105. [Google Scholar] [CrossRef]
  70. Ulrich, R.S.; Simons, R.F.; Losito, B.D.; Fiorito, E.; Miles, M.A.; Zelson, M. Stress recovery during exposure to natural and urban environments. J. Environ. Psychol. 1991, 11, 201–230. [Google Scholar] [CrossRef]
  71. McGee, B.; Park, N.K. Colour, light, and materiality: Biophilic interior design presence in research and practice. Interiority 2022, 5, 27–52. [Google Scholar] [CrossRef]
  72. Hartig, T.; Evans, G.W.; Jamner, L.D.; Davis, D.S.; Gärling, T. Tracking restoration in natural and urban field settings. J. Environ. Psychol. 2003, 23, 109–123. [Google Scholar] [CrossRef]
  73. Ulrich, R.S. Nature versus urban scenes: Some psychophysiological effects. J. Environ. Behav. 1981, 13, 523–556. [Google Scholar] [CrossRef]
  74. Shuda, Q.; Bougoulias, M.E.; Kass, R. Effect of nature exposure on perceived and physiologic stress: A systematic review. Complement. Ther. Med. 2020, 53, 102514. [Google Scholar] [CrossRef]
  75. Fallon, V.T.; Rubenstein, S.; Warfield, R.; Ennerfelt, H.; Hearn, B.; Leaver, E. Stress reduction from a musical intervention. Psychomusicology Music. Mind Brain 2020, 30, 20. [Google Scholar] [CrossRef]
  76. Correia, P.; Quaresma, C.; Morais, P.; Fonseca, M.; Vigário, R.; Quintao, C. Effects of mindfulness-based stress reduction meditation on the emotional reaction to affective pictures assessed by electrodermal activity. Biomed. Signal Process. Control 2023, 86, 105314. [Google Scholar] [CrossRef]
  77. Setz, C.; Arnrich, B.; Schumm, J.; La Marca, R.; Tröster, G.; Ehlert, U. Discriminating stress from cognitive load using a wearable EDA device. IEEE Trans. Inf. Technol. Biomed. 2009, 14, 410–417. [Google Scholar] [CrossRef] [PubMed]
  78. Dawson, M.E.; Schell, A.M.; Filion, D.L. The electrodermal system. Handb. Psychophysiol. 2007, 2, 200–223. [Google Scholar]
  79. Gray, T.; Birrell, C. Are biophilic-designed site office buildings linked to health benefits and high performing occupants? Int. J. Environ. Res. Public Health 2014, 11, 12204–12222. [Google Scholar] [CrossRef] [PubMed]
  80. Al Khatib, I.; Samara, F.; Ndiaye, M. A systematic review of the impact of therapeutical biophilic design on health and wellbeing of patients and care providers in healthcare services settings. Front. Built Environ. 2024, 10, 1467692. [Google Scholar] [CrossRef]
  81. Miola, L.; Boldrini, A.; Pazzaglia, F. The Healing Power of Nature. Biophilic Design Applied to Healthcare Facilities. Curr. Opin. Psychol. 2025, 64, 102049. [Google Scholar] [CrossRef]
  82. Chan, S.H.M.; Qiu, L.; Esposito, G.; Mai, K.P.; Tam, K.P.; Cui, J. Nature in virtual reality improves mood and reduces stress: Evidence from young adults and senior citizens. Virtual Real. 2023, 27, 3285–3300. [Google Scholar] [CrossRef]
  83. Clemente, D.; Romano, L.; Russo, C.; Carrus, G.; Panno, A. 3D built virtual arctic environment increase vigor through connectedness in older people. Sci. Rep. 2024, 14, 23432. [Google Scholar] [CrossRef]
  84. Şansal, K.E.; Şimşek, A.C.; Aktan, S.; Özbey, F.; Paksoy, A. Restorative effects of virtual nature on the emotional well-being of community-dwelling older adults. Eur. J. Geriatr. Gerontol. 2024, 6, 12–18. [Google Scholar] [CrossRef]
  85. Pardini, S.; Gabrielli, S.; Gios, L.; Dianti, M.; Mayora-Ibarra, O.; Appel, L.; Olivetto, S.; Torres, A.; Rigatti, P.; Trentini, E.; et al. Customized virtual reality naturalistic scenarios promoting engagement and relaxation in patients with cognitive impairment: A proof-of-concept mixed-methods study. Sci. Rep. 2023, 13, 20516. [Google Scholar] [CrossRef] [PubMed]
  86. Sadowski, I.; Meilleur-Bédard, M.; Khoury, B. A novel virtual reality-based nature meditation program for older adults’ mental health: Results from a pilot randomized controlled trial. Clin. Gerontol. 2025, 1–21. [Google Scholar] [CrossRef] [PubMed]
  87. Kalantari, S.; Bill Xu, T.; Mostafavi, A.; Lee, A.; Barankevich, R.; Boot, W.R.; Czaja, S.J. Using a nature-based virtual reality environment for improving mood states and cognitive engagement in older adults: A mixed-method feasibility study. Innov. Aging 2022, 6. [Google Scholar] [CrossRef] [PubMed]
Buildings 15 03466 g001
Figure 1. The five rooms, according to the participant’s perspective, namely: the Nature room (top left); the Comfort-nature room (top right); and the Comfort room (bottom left), i.e., environments inspired by nature; The Modern and Basic rooms (bottom right), i.e., the urban-like environments.
Figure 1. The five rooms, according to the participant’s perspective, namely: the Nature room (top left); the Comfort-nature room (top right); and the Comfort room (bottom left), i.e., environments inspired by nature; The Modern and Basic rooms (bottom right), i.e., the urban-like environments.
Buildings 15 03466 g001
Buildings 15 03466 g002
Figure 2. The graphs show the average positive (left panel) and negative (right panel) ratings as a function of the type of room. The red asterisk indicates the condition(s) that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Figure 2. The graphs show the average positive (left panel) and negative (right panel) ratings as a function of the type of room. The red asterisk indicates the condition(s) that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Buildings 15 03466 g002
Buildings 15 03466 g003
Figure 3. The graph shows the percentage variation of EDA levels from the baseline (Δ%) as a function of the type of room. The red asterisk with the red line indicates the conditions that significantly differ from all others. The error bars represent the standard error.
Figure 3. The graph shows the percentage variation of EDA levels from the baseline (Δ%) as a function of the type of room. The red asterisk with the red line indicates the conditions that significantly differ from all others. The error bars represent the standard error.
Buildings 15 03466 g003
Buildings 15 03466 g004
Figure 4. The graphs show the average positive ratings as a function of the type of room and sound. The red asterisk indicates the conditions that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Figure 4. The graphs show the average positive ratings as a function of the type of room and sound. The red asterisk indicates the conditions that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Buildings 15 03466 g004
Buildings 15 03466 g005
Figure 5. The graphs show the average negative ratings as a function of the type of room and sound. The red asterisk indicates the condition(s) that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Figure 5. The graphs show the average negative ratings as a function of the type of room and sound. The red asterisk indicates the condition(s) that significantly differ from all others. The black asterisk and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Buildings 15 03466 g005
Buildings 15 03466 g006
Figure 6. The graphs show the percentage variation of EDA levels from the baseline (Δ%) as a function of the type of room and sound. The red asterisk with the red line indicates the conditions that significantly differ from all others. The black asterisks and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Figure 6. The graphs show the percentage variation of EDA levels from the baseline (Δ%) as a function of the type of room and sound. The red asterisk with the red line indicates the conditions that significantly differ from all others. The black asterisks and the dashed line indicate the conditions that significantly differ from each other. The error bars represent the standard error.
Buildings 15 03466 g006
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Rapuano, M.; Ruotolo, F.; Cannito, L.; Masullo, M.; Cioffi, F.; Ruggiero, G.; Maffei, L.; Capitelli, F.; Iachini, T. Calm by Design: Nature-Inspired Rooms Reduce Electrodermal Activity Levels. Buildings 2025, 15, 3466. https://doi.org/10.3390/buildings15193466

AMA Style

Rapuano M, Ruotolo F, Cannito L, Masullo M, Cioffi F, Ruggiero G, Maffei L, Capitelli F, Iachini T. Calm by Design: Nature-Inspired Rooms Reduce Electrodermal Activity Levels. Buildings. 2025; 15(19):3466. https://doi.org/10.3390/buildings15193466

Chicago/Turabian Style

Rapuano, Mariachiara, Francesco Ruotolo, Loreta Cannito, Massimiliano Masullo, Federico Cioffi, Gennaro Ruggiero, Luigi Maffei, Fabiola Capitelli, and Tina Iachini. 2025. "Calm by Design: Nature-Inspired Rooms Reduce Electrodermal Activity Levels" Buildings 15, no. 19: 3466. https://doi.org/10.3390/buildings15193466

APA Style

Rapuano, M., Ruotolo, F., Cannito, L., Masullo, M., Cioffi, F., Ruggiero, G., Maffei, L., Capitelli, F., & Iachini, T. (2025). Calm by Design: Nature-Inspired Rooms Reduce Electrodermal Activity Levels. Buildings, 15(19), 3466. https://doi.org/10.3390/buildings15193466

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop