Feasibility of Combining Transcranial Direct Current Stimulation and Active Fully Embodied Virtual Reality for Visual Height Intolerance: A Double-Blind Randomized Controlled Study.

Samuel Bulteau,Samuel Bulteau,Samuel Bulteau,Samuel Bulteau,Yannick Prié,Yannick Prié,Yannick Prié,Florian Melki,Florian Melki,Florian Melki,Andrew Laurin,Didier Acier,Morgane Péré,Thomas Rabeyron,Élodie Faurel-Paul,Olivier Charlet,Anne Sauvaget,Anne Sauvaget,Marie-Anne Vibet,Jean-Benoit Hardouin,Toinon Vigier,Toinon Vigier,Toinon Vigier,Matthieu Perreira Da Silva,Matthieu Perreira Da Silva,Matthieu Perreira Da Silva,Valéry-Pierre Riche,Véronique Sebille,Lydie Lagalice,Kalyane Bach-Ngohou,Kalyane Bach-Ngohou

doi:10.3390/jcm11020345

Abstract

Background: Transcranial Direct Current Stimulation (tDCS) and Virtual Reality Exposure Therapy (VRET) are individually increasingly used in psychiatric research. Objective/Hypothesis: Our study aimed to investigate the feasibility of combining tDCS and wireless 360° full immersive active and embodied VRET to reduce height-induced anxiety. Methods: We carried out a pilot randomized, double-blind, controlled study associating VRET (two 20 min sessions with a 48 h interval, during which, participants had to cross a plank at rising heights in a building in construction) with online tDCS (targeting the ventromedial prefrontal cortex) in 28 participants. The primary outcomes were the sense of presence level and the tolerability. The secondary outcomes were the anxiety level (Subjective Unit of Discomfort) and the salivary cortisol concentration. Results: We confirmed the feasibility of the association between tDCS and fully embodied VRET associated with a good sense of presence without noticeable adverse effects. In both groups, a significant reduction in the fear of height was observed after two sessions, with only a small effect size of add-on tDCS (0.1) according to the SUD. The variations of cortisol concentration differed in the tDCS and sham groups. Conclusion: Our study confirmed the feasibility of the association between wireless online tDCS and active, fully embodied VRET. The optimal tDCS paradigm remains to be determined in this context to increase effect size and then adequately power future clinical studies assessing synergies between both techniques.

Highlights

Anxiety disorders affect about one third of the general population and are associated with significant distress and impairment due to excessive and persistent fear and/or anxiety and related behavioral disturbance, including avoidance mechanisms [1,2,3]
This study was conducted using a randomized, double-blind and controlled betweensubjects design comparing the effect of two sessions of Virtual Reality Exposure Therapy (VRET) combined with active or sham Transcranial Direct Current Stimulation (tDCS)
Towards Heights Questionnaire; HIQ: Height Interpretation Questionnaire; STAI: State-Trait Anxiety; Subjective Unit of Distress (SUD): Subjective Unit of Discomfort; Visual Height Intolerance Severity Scale (vHISS): visual Height Intolerance Severity Scale. This is the largest proof of concept study regarding anxiety using online, simultaneous, wireless tDCS and a fully active and immersive VR task

Summary

Introduction

Anxiety disorders affect about one third of the general population and are associated with significant distress and impairment due to excessive and persistent fear and/or anxiety and related behavioral disturbance, including avoidance mechanisms [1,2,3]. Exposure therapy is based on fear extinction learning, enabling patients’ anxiety to be decreased [13,14,15] In this regard, the efficacy of virtual reality exposure therapy (VRET), which consists of immersing the subject in a computer-generated virtual environment, has shown promise in treating a variety of anxiety disorders [16,17] and may be as effective as in vivo exposure therapy for patients suffering from acrophobia [18]. Results: We confirmed the feasibility of the association between tDCS and fully embodied VRET associated with a good sense of presence without noticeable adverse effects In both groups, a significant reduction in the fear of height was observed after two sessions, with only a small effect size of add-on tDCS (0.1)

Methods

Discussion

Conclusion