Effects of tDCS Combined With VR on Anxious Ruminations in Healthy Subjects With a Vulnerability to Rumination

Inclusion visit:

• Confirmation of eligibility criteria
• Written informed consent

Visit 1 and 2 (or end of study visit) :

Before first ruminations induction :

• Completion of Brief State Rumination Inventory (BSRI), State-Trait Anxiety (STAI), Inventory, Visual Analogic Scale (VAS), Ruminative Response Scale - Short Form (RRS-SF), Beck depression Inventory (BDI)
• EEG recording

Then Procedure for inducing ruminations using a pre-recorded voice listened to in an audio headset alternating statements promoting a positive, neutral and negative introspection and self-judgment attitude (the latter are heard at the end to initiate the rumination process) over 8 minutes

Then

• Completion of Brief State Rumination Inventory (BSRI), Inventory, Visual Analogic Scale (VAS), Beck depression Inventory (BDI),
• EEG recording
• Pulse and blood pressure measurements

Then immersion in a relaxing virtual environment for 20 minutes with active or sham placebo.

• Cutaneous conductance measurement and eye-tracking during immersion

At the end of immersion :

• Completion of Brief State Rumination Inventory (BSRI), Inventory, Visual Analogic Scale (VAS), Beck depression Inventory (BDI), IGroup presence questionnaire (IPQ)
• Pulse and blood pressure measurements

Then again procedure for inducing ruminations .

At the end of ruminations induction :

• Completion of Brief State Rumination Inventory (BSRI), State-Trait Anxiety (STAI), Inventory, Visual Analogic Scale (VAS), Beck depression Inventory (BDI), tolerance questionnaires
• Debriefing

Inclusion criteria

• Without any particular ethnic and psychosocial criteria
• Subject to ruminations (personality trait) documented by a RRS-SF score >30
• Subjects with score to BDI scal <14 assessed during first visit
• Subjects without psychiatric or addictive disorders.
• Subjects who do not meet all the diagnostic criteria for an anxiety disorder or characterized depressive episode.

Exclusion criteria

• contraindication to tDCS (neurosurgical history, intracranial device, skin problems)
• current virtual reality intolerance
• history of psychiatric or addictive disorders
• Use of psychotropic drugs
• Use of non psychotropic treatments significantly influencing mood or level of anxiety
• pregnant or breast-feeding women
• Neurological pathology, locomotor disability, or sensory (vestibular, visual, auditory ...)