Effects of virtual fear on real anxiety - Effects of exposure in virtual reality and in vivo on anxiours healthy participants in narrow rooms

In vivo exposure is a highly effective but rarely implemented treatment for agoraphobia. Most of the patients receive medication or cognitive therapy without exposure because of a high expenditure of money and time for in vivo exposure. Exposure in virtual reality (VR) is easier to implement but the effectiveness of stimulating fear compared to in vivo exposure is still questionable. Therefore, in this study, the effects of in vivo and VR exposure on subjective symptom burden and heart rate variability (HRV) were assessed. 30 healthy individuals with fears in narrow rooms went through in vivo and VR exposure in a randomized order while HRV parameters (RMSSD, HF) and subjective symptom burden was assessed. Linear mixed models were calculated. The effect of condition (VR vs. in vivo), scenario (several narrow rooms) and slot (first 30 seconds, peak, last 30 seconds) on RMSSD and HF was assessed. A random effect for participants (random-intercept term) to allow the intercept to vary across participants was included. Regarding RMSSD and HF, participants showed significantly higher levels during in vivo exposure compared to exposure in VR (RMSSD: p = .005; HF: p < .001), reflecting a stronger activation of the parasympathetic nervous system during in vivo exposure or presumably higher stress levels during VR exposure. This study highlights the necessity of assessing subjective and objective parameters allowing the evaluation of the effectiveness of fear stimulation by exposure approaches. The effectiveness of VR exposure for agoraphobic patients' needs to be assessed in future studies. ### 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 of 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I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the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