Effects of Biophilic Design interventions on university students' cognitive performance: An audio-visual experimental study in an Immersive Virtual office Environment

The human-nature connection should be a key component in the design of supportive and comfortable indoor environments. An interest in introducing Nature Based Solutions indoor via Biophilic Design (BD) intervention recently emerged. Related benefits for work efficiency have been identified in lab-studies without the possibility to perform preliminary design assessments. Recently, VR has been adopted thanks to its advantages for data collection in highly realistic environments. To date, most of the research on BD has been focused on the visual connection with nature even if people experience multiple senses simultaneously. In this paper, a new design approach for preliminary assessment of BD intervention in VR is presented. A 3x3 between-subjects design study is presented, comparing three office layouts (Indoor Green, Outdoor Green and Non-Biophilic) and three acoustic scenarios (Office, Office + Traffic and Office + Nature). 198 participants performed one test session completing three cognitive tasks for each acoustic condition, and survey. The results of the sense of presence and immersivity (visual), the sensory congruency (acoustic) and cybersickness disorders suggested that VR is an effective tool to preliminary evaluate the potential of BD interventions (ecological validity). The findings of the cognitive tests revealed that audio-visual connection with nature can positively influence working memory, inhibition and taskswitching performance. The acoustic factor exhibited a higher improvement effect compared to the visual factor, between 23 % and 71 % against 12 %-39 %. Moreover, the Natural sound in the Indoor Green condition was the most supportive visual*acoustic condition while Traffic in the Non-Biophilic environment was the most disruptive one.