Adapted from: Scientific Reports volume 13, Article number: 1239 (2023) 

 

Abstract

 

Exposure to natural environments offers an array of mental health benefits. Virtual reality provides simulated experiences of being in nature when outdoor access is limited. Previous studies on virtual nature have focused mainly on single “doses” of virtual nature. The effects of repeated exposure remain poorly understood.

 

Motivated by this gap, we studied the influence of a daily virtual nature intervention on symptoms of anxiety, depression, and an underlying cause of poor mental health: rumination. Forty college students (58% non-Hispanic White, median age = 19) were recruited from two U.S. universities and randomly assigned to the intervention or control group.

 

Over several weeks, anxious arousal (panic) and anxious apprehension (worry) decreased with virtual nature exposure. Participants identifying as women, past VR users, experienced with the outdoors, and engaged with the beauty in nature benefited particularly strongly from virtual nature. Virtual nature did not help symptoms of anhedonic depression or rumination. Further research is necessary to distinguish when and for whom virtual nature interventions impact mental health outcomes.

 

Key takeaways

 

  • “Exposure to natural environments can improve mental health. At least 17 systematic reviews have summarized the growing literature on this topic1. […] Some of the strongest associations between nature exposure and health are seen for anxiety and depression, with 33% and 37% less relative risk for people living in greener neighborhoods2.”
  • “Virtual nature involves pictures, videos, or immersive media (i.e., virtual reality [VR] headsets) presenting audio–video or multisensory simulations of natural environments11. […] Audiovisual combinations promote greater psychological benefits than audio or visual sensory inputs alone13. Correspondingly, researchers are increasingly studying simulated nature in VR headsets rather than other media11.”
  • “We conducted one of the first longitudinal experiments of daily virtual nature exposure and clinical measures of mental health, namely symptoms of anxiety and depression and a potential cause of depression: rumination. Among our sample of 40 college students, anxious apprehension (worry) decreased with virtual nature exposure relative to no exposure.”
  • “Our study and others that failed to find benefits of repeated exposure [for depression] provided no interactive opportunities21,22. Interactions may distract participants from negative emotions by refocusing attention. Comparatively, non-interactive and interactive experiences may activate the parasympathetic nervous system through relaxation, which may alleviate anxiety symptoms.”
  • “The findings of this study reinforce a growing body of literature that finds virtual nature is an effective, safe, and acceptable intervention for mental health promotion15. While actual outdoor nature is likely to have stronger effects than virtual nature, virtual nature can produce an array of beneficial effects10. These extend beyond physiological, affective, and cognitive restoration to social, ecological, and “transcendent” (altered state of consciousness, or revelations where the self and environment are perceived anew) restoration50.”
  • “Virtual nature should be offered to populations who do not have safe access to outdoor settings due to psychological, physical, residential, or other barriers. In particular, virtual nature could be recommended to clinical populations16 and people living and working in isolated and confined environments (i.e., polar regions, submarines, cargo ships, and outer space)7,8.”

 

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Data availability

 

The datasets generated and analyzed during the current study and the scripts used to generate the results are available on the Open Science Framework (OSF) at https://osf.io/r73x5/ (https://doi.org/10.17605/OSF.IO/R73X5).

 

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Acknowledgements

 

We would like to thank VR@Illinois and the Campus Research Board at the University of Illinois at Urbana-Champaign (UIUC) for sponsoring this research. We also extend thanks for in-kind support from the following units: UIUC Department of Psychology; UIUC Department of Recreation, Sport and Tourism; UIUC Department of Natural Resources and Environmental Sciences; Clemson University Department of Communications; and Clemson University Department of Parks, Recreation & Tourism Management. Additional thanks goes to our UIUC pilot study participants, including Wendy Hsieh, Lulia Fratila, Guangzhou Chen, Milae Lee, Violet Yoon, and John Zaczorowski. Finally, special thanks go to Marianne Herr, Principal Lecturer in the Department of Communications at Clemson University, for participant recruitment.

 

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Authors and Affiliations

  1. Virtual Reality and Nature Lab, Clemson University, Clemson, SC, USA Matthew H. E. M. Browning, Olivia McAnirlin, Shuai Yuan & Vishnunarayan Girishan Prabhu
  2. Department of Parks, Recreation and Tourism Management, Clemson University, Clemson, SC, USA Matthew H. E. M. Browning, Olivia McAnirlin, Ryan J. Gagnon & Shuai Yuan
  3. Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA Seunguk Shin
  4. College of Education, University of Illinois at Urbana-Champaign, Champaign, IL, USA Gabrielle Drong
  5. School of Mathematical and Statistical Sciences, Clemson University, Clemson, SC, USA Shyam Ranganathan
  6. University of North Florida, Jacksonville, FL, USA Kailan Sindelar
  7. INVIROVR Inc., Santa Fe, NM, USA David Hoptman
  8. School of Environmental and Forest Sciences, University of Washington, Seattle, WA, USA Gregory N. Bratman
  9. Systems Engineering and Engineering Management, University of North Carolina at Charlotte, Charlotte, NC, USA Vishnunarayan Girishan Prabhu
  10. Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL, USA Wendy Heller

 

Contributions

M.B. was responsible for the concept and design of the work, data analysis, interpretation of results, and the first draft of the manuscript. S.S., G.D., O.M., D.H., and W.H. assisted with designing the work, collecting data, and revising the manuscript. D.H. was also responsible for the creation of the VR simulations. K.S. and S.Y. assisted with data collection and revised the manuscript. R.G., S.R., G.B., and V.P. assisted with data analysis, interpretation of results, and revising the manuscript.

 

Corresponding author

Correspondence to Matthew H. E. M. Browning.

 

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