Stress reaction
None of biophilic interventions showed significant improvement in objective physiological indicators. This is likely due to the small effect sizes, which in turn led to a small power for our study. All the effect sizes were smaller than 0.2 (However, there were two discrepancies worth discussing. Firstly, some interventions had similar physiological changing patterns, though the results were not significant. Indoor Green and Outdoor Green induced similar changes in stress indicators except for SBP, while Turbid Outdoor Green and Combination had similar measurement changes except for SCL. Research shows that people’s perceived restorativeness of natural environments can be influenced by their feelings of connectedness to nature [Secondly, participants self-reported significantly lower stress levels after exposure to biophilic interventions, which is contradictory to the non-significant changes in the physiological measurements. This also happened in Verzwyvelt et al.’s study on oncology patients who reported more willingness to contact nature, but no significant stress relief responses were found physiologically [Another interesting finding is the consistently higher BP means across all biophilic interventions. This increase, although not statistically significant, may be caused by the absence of stress induction during the experiment. It also explains the contradiction with previous studies which found restorative effects of biophilic environments on BP through immersive video either shown on TV [