Physiological and psychological responses to transitions between urban built and natural environments using the cave automated virtual environment

Observational and experimental studies have illustrated that exposure to greenness is beneficial to long-term health and well-being. In the urban context, however, more evidence is needed for a better understanding of the short-term health impacts of nearby nature. To address this limitation, we investigated the dynamic influence of transitions between built and natural environments on urban residents using Cave Automated Virtual Environment (CAVE) immersive virtual reality technology. In this experiment, we filmed two pairs of 360 degrees 8K videos of geographically adjacent built and natural environments in Boston, MA to mimic real-life environmental exposure of urban residents, and created virtual immersive stimuli with an 8K-resolution curved panoramic screen accompanied with a 7.2 Dolby Surround 360 degrees audio system. We recruited 171 participants in a randomized crossover experiment to evaluate physiological and psychological responses to transitions between urban built and natural environments. Our psychological results indicate significant reductions in negative mood dimensions, total mood disturbance, and transient anxiety, during the transition from built to natural environments; and increases during the transition from natural to built environments. In addition, we observed participants showed more emotional responses to nature through physiological measures. Lastly, we found that contextual factors that were rarely tested in previous studies, including differential physical health conditions, underlying stress levels, formative experience with nature, and growth environments, might influence the extent of stress recovery. This study provided empirical evidence from the health perspective for promoting nearby nature in urban built environments.