Effects of exposure in virtual reality and in vivo on subjective symptom burden and physiological parameters of height-anxious healthy participants - A pilot study

Exposure in vivo is a highly effective treatment for anxiety disorders and acrophobia in particular. Nevertheless, it is rarely implemented in outpatient treatment. Exposure in virtual reality (VR) might be an alternative but its effect on subjective symptom burden and physiological parameters is questionable. Therefore, in this study, N = 33 participants with fear of heights received both in vivo and VR exposure in a randomized order. Subjective symptom burden before and after each exposure as well as heart rate and heart rate variability (SDNN, LF/HF ratio) during exposure sessions were assessed. Linear mixed models were calculated with the effect of condition (VR vs. in vivo) and scenario on HR, SDNN and LF/HF ratio. Subjective symptom burden was significantly reduced after both exposure sessions (p = .002; p < .001). Heart rate was significantly higher during exposure scenarios than baseline (p < .001). SDNN and LF/HF ratio reflected a significantly higher general power of HRV and a significantly higher activation of the sympathetic nervous system during exposure sessions compared to baseline and during VR exposure compared to in vivo. All in all, VR exposure shows comparable or superior effects compared to in vivo exposure regarding acrophobic fears and physiological parameters. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee of Landesaerztekammer Rheinland-Pfalz (regional medical association Rhineland-Palatinate) gave ethical approval for this work. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors