Assessing Dissociation in Hypnosis and Virtual Reality Hypnosis: A Comparative Study in Healthy Participants

Hypnosis has long been recognized as a useful tool in clinical applications. During hypnosis, one can experience a particular phenomenology that is characterized by absorption in the experience, dissociation (i.e., separation of perceived perceptions from the external environment), a modified sense of agency (i.e., automaticity), and increased suggestibility (i.e., unconditional acceptance of suggestions). With the recent advancements in virtual reality technology, incorporating hypnosis into immersive virtual environments has become a promising way to enhance therapeutic interventions and deepen our understanding of the neuro-psychological processes involved in hypnosis. The primary objective of this study is to evaluate the potential impacts of virtual reality hypnosis (VRH) on the dissociation of healthy volunteers. More precisely, this study, which is a non-inferiority randomized trial, aims to demonstrate that dissociation state can be reached with the new technique of VRH, as already demonstrated with hypnosis.
The study included 66 healthy participants (age = 41,2y ± 14,4y; 38 women). In a randomized order, each participant received 15 minutes of hypnosis and 15 minutes of VRH. The hypnosis session consisted of a prerecorded hypnotic exercise called "safe place," in which participants were instructed to find a location where they feel at peace. Participants in this session listened to the exercise through headphones while wearing a VR headset that showed a black cross that they had to fixate. The VRH session consisted of an immersion in a virtual reality submarine environment (Aqua, Oncomfort). Participants had to follow a whale and breathe along with the rhythms of its tail. Hypnotic suggestions delivered in VRH were similar to those delivered in hypnosis (i.e., comfort and relaxation). Visual Analog Scale (VAS, 0-10) about dissociation, absorption, automaticity, alertness, and an open-ended question about time perception were asked after each session. Anxiety was assessed before and after each session (VAS, 0-10).
Repeated measures ANOVAs were performed. Results revealed no statistically significant differences in dissociation (p=0.29), absorption (p=0.26), automaticity (p=0.29), alertness (p=0.09) or time perception (p=0.78) between the hypnosis and VRH sessions. Additionally, there were non-statistical differences in anxiety before and after each session. These results suggest that in healthy participants, VRH induces comparable levels of dissociation, absorption, alertness, automaticity, time perception and anxiety as does hypnosis.
The present study highlights the potential of virtual reality as an effective device for delivering hypnosis interventions, suggesting that it can be a useful tool for researchers and clinicians seeking to explore and utilize the benefits of hypnosis.