Optimizing Virtual Nature for Psychological and Physiological Well-Being: A Systematic Review of the Moderating Effects of Duration, Nature Type, Sample Characteristics, and Immersiveness and Potential Risks of Bias

Virtual nature research has emerged as a prominent and captivating study area, gaining much attention for its profound potential to enhance well-being. This literature review aimed to expand prior reviews of virtual nature experiences on psychological and physiological well-being in two ways: summarizing how four factors may moderate the beneficial effects of virtual nature and reporting the risk of bias in this body of literature. Searches for peer-reviewed research articles were conducted in Web of Science and Scopus and manually identified, returning 78 relevant empirical studies published between 2010 and 2023. The assessment of bias was conducted utilizing Cochrane's RoB 2 and ROBINS-I tools. The four moderators examined were duration of exposure (i.e., <= 5 min, 5-10 min, >= 10 min), type of virtual nature (i.e., green space, blue space), sample characteristics (i.e., age, health status), and immersion level (i.e., virtual reality [VR], 2D screens). We found limited evidence for the impact of the first three moderators but stronger evidence for higher levels of immersion showing stronger benefits. All studies were found to have a moderate to high risk of bias, mostly related to the subjective measurement of outcomes. Future research should prioritize studying tailored virtual nature interventions and their long-term effects among diverse participants and different types of virtual environments, as well as investigating the influence of presence and immersion levels in virtual settings. These efforts will provide further insights into the underlying mechanisms of the benefits derived from virtual nature exposure.