Effects of Virtual Nature Embodiment on Compassion, Empathy, Nature Connectedness, and Symptom Burden in Patients...

Nature experiences may have a positive impact on mental health. Innovative alternatives, such as immersive virtual reality (iVR), can have similar effects. In previous studies on embodying a tree in virtual reality, connectedness to nature has been induced in healthy participants and shown to be influenced by compassion. Compassion and empathy, however, can be altered in psychiatric disorders, leading to impaired relationships with fellow human beings. The potential effect of nature experiences in iVR on compassion, empathy, and nature connectedness in mental health disorders has not yet been investigated.

This study aims to examine the development of nature connectedness, compassion, empathy, and individual symptom load in patients with depression (n=20), schizophrenia (n=20), and healthy controls (n=20), measured pre and post 1 session of virtual embodying a rainforest tree.

We conducted an explorative clinical trial, comparing 3 groups (depression, schizophrenia, and healthy control), using repeated measures ANOVA and multiple regression analysis. Effect sizes (η_p²) and 95% CIs were reported where applicable. We assessed the impact of iVR-exposure on nature connectedness, empathy, compassion, individual symptoms, spirituality, cybersickness, presence, and virtual body ownership. Electrodermal activity was measured to capture physiological correlates of emotional arousal.

Individual symptom load decreased significantly through the experience of embodying a growing tree in iVR in both patient groups (F_1,38=40.93, η_p²=0.52, 95% CI 0.29-0.67; P<.001). All groups benefited equally from the iVR experience regarding a change in nature connectedness (F_1,57=100.12, η_p²=0.637, 95% CI 0.48-0.74; P<.001) and compassion (F_1,57=12.86, η_p²=0.18, 95% CI 0.04-0.36; P<.001). The change in empathy did not differ significantly between the 3 groups. The analysis of electrodermal activity during iVR showed significantly higher nonspecific skin conductance response numbers than at the beginning of the iVR (2-tailed t₅₃=4.40, mean difference=2.38, 95% CI 1.30-3.46; P<.001). Changes in compassion were predicted by spirituality (β=-0.35, 2-tailed t₅₉=-2.89, η_p²=0.13, 95% CI 0.01-0.30; P=.005) and virtual body ownership (β=0.29, 2-tailed t₅₉=2.15, η_p²=0.08, 95% CI 0.00-0.23; P=.04) but not by the feeling of presence.

Our results indicate that virtually embodying a tree seems to have a positive effect on individual symptoms. Patients with depression and schizophrenia were able to receive an iVR-based intervention and benefited from the experience. Our results provide a deeper understanding of the phenomenon of virtual body ownership of nature, a specific affordance of iVR, thereby laying the groundwork for future innovative body psychotherapy interventions for individuals with mental health disorders.

ClinicalTrials.gov NCT06446856; https://tinyurl.com/nhjar26p.