Virtual reality application to explore indoor soundscape and physiological responses to audio-visual biophilic design interventions: An experimental study in an office environment

Among the major sources of disturbance in offices, noise and poor acoustics consistently rank at the top. Moreover, the positive impact which connecting with nature has on individuals is welldocumented, yet still not investigated in-depth in terms of office soundscapes. In the present study, a methodology using Virtual Reality (VR) technology is employed to analyse the benefits of Biophilic Design interventions in office spaces. Notably, the study investigates the independent and interaction effects of audio-visual connection with nature on 1) office soundscape, and 2) physiological parameters, and 3) explores potential correlations between physiological and soundscape response. Three different visual scenarios (Indoor Green, Outdoor Green and NonBiophilic) and three sound environments (Office - O, Office + Traffic - O + T and Office + Nature - O + N) for a virtual office environment were combined in a between-subjects design experiment. During their exposure to each acoustical scenario, 198 participants' responses on perceived affective quality of soundscapes (ISO/TS 12913-2) and physiological reactions (ElectroDermal Activity - EDA, Pulse Rate - PR, Skin Temperature -ST) were collected. The results show a major effect of the sound factor on soundscape assessment, with the O + N scenario resulting in increased pleasantness and eventfulness compared to the O scenario, i.e. a more vibrant office soundscape. Moreover, an interaction between sound and visual stimuli on pleasantness was detected, with IG being more effective in O + N, while OG being more beneficial in the O + T scenario. Significant positive physiological responses were more elicited in the presence of an acoustical connection with nature than a visual one: pleasant soundscapes of nature were associated with lowered EDA and PR with an additional improvement in EDA in the presence of indoor greenery. Moreover, a more pleasant sound (O + N) tended to decrease skin temperature in the presence of indoor greenery, while a more unpleasant and eventful acoustical scenario (O + T) gave the largest PR increase in the absence of nature-related elements indoors. This research provides first insights for the biophilic design of office spaces through nature-related audio-visual stimuli.