The effect of visual and auditory biophilic design interventions on cognitive performance in office workers: A multiple cohort crossover study in a living lab

Abstract

Background: People spend most of their time indoors, limiting exposure to natural environments that negatively impact occupants, including cognition. Biophilic design is one strategy to integrate natural elements to indoor environments, though the research has focused predominantly on the impact of visual biophilic elements, like plants. The current study measured the impact of both visual and auditory biophilic design elements on cognitive performance. Auditory biophilic elements consisted of regionally specific nature sounds (e.g. running water, wind, local birds) played from overhead speakers. Visual biophilic elements included physical plants and rotating digital images of natural landscapes. Methods: Thirty-seven office-workers across three cohorts relocated to the lab, where they performed their regular work duties for 10 weeks in a simulated office environment. After a two-week acclimation period, participants experienced each condition (baseline, visual-only, audio-only, and multimodal) for a one-week period twice in a randomized order. Impacts on cognition were measured through executive function tasks, including working memory (WM), response inhibition (RI), and task switching (TS). Results: Linear mixed effects models were used to assess the relationship between each condition and cognitive performance. Compared to control, WM score improved in the visual (B = 0.056, p = .003), audio (B = 0.070, p < .001), and multimodal (B = 0.061, p = .001) conditions. The RI task response time improved in all biophilia conditions (visual B = -17.255, audio B = -34.594, multimodal B = -21.604, p < .001 for all). TS response time was faster in the audio condition (B = -14.135, p = .006), but slower in the multimodal condition (B = 10.599, p = .032). Conclusion: In sum, there were differential improvements in cognitive performance across the three biophilic conditions, suggesting both audio and visual elements can improve aspects of cognition and should be explored for future building design.