An interventional study of tDCS session and symptom provocation in Obsessive - Compulsive Disorder, sponsored by Centre Hospitalier Henri Laborit. Not yet recruiting at 6 sites in France. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-10-21.
Sponsored by Centre Hospitalier Henri Laborit · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to learn if symptom provocation before transcranial Direct Current Stimulation (tDCS) in Obsessive-Compulsive Disorder (OCD) patients. The main question it aims to answer is:
Can symptom-provocation before tDCS improve therapeutic response in OCD patients ?
Researchers will compare the clinical outcomes of OCD patients having received, in one arm, tDCS and, in the other arm, patients having received tDCS preceded by symptom provocation to see if therapeutic response and various other clinical variables differ.
Obsessive-compulsive disorder (OCD) is a chronic and disabling condition affecting 2-3% of the population. Despite evidence-based interventions-cognitive behavioural therapy with exposure and response prevention (ERP) and serotonergic antidepressants, 40-60% of patients exhibit insufficient improvement, highlighting a substantial need for more effective therapeutic strategies.
Neuroimaging and neurophysiological studies consistently implicate dysfunction within cortico-striato-thalamo-cortical circuits, particularly the supplementary motor area (SMA) and orbitofrontal cortex (OFC). These findings have guided the development of neuromodulation interventions targeting these regions. Among them, transcranial direct current stimulation (tDCS) has emerged as a safe, accessible, and potentially effective approach for modulating aberrant neural activity in OCD.
Our research group has previously investigated a bifocal tDCS montage combining cathodal SMA stimulation with anodal right OFC stimulation. In an open-label study of 21 patients, this protocol produced clinically meaningful improvement in 15% of participants and was well tolerated. A subsequent multicentre randomised controlled trial confirmed the feasibility, safety, and potential therapeutic value of this montage, although overall effects remained modest. These findings underscore the need to optimise neuromodulatory strategies in OCD.
One promising direction is to enhance neuromodulation by manipulating the pre-stimulation neural state. Evidence suggests that the impact of tDCS depends on ongoing cortical activity, raising the possibility that activating symptom-relevant circuits immediately before stimulation could potentiate its effects. Pre-stimulation symptom provocation-also referred to as paired associative cognitive stimulation-has shown encouraging results when combined with rTMS in depression, addiction, and post-traumatic stress disorder (PTSD). In PTSD, for example, brief reactivation of traumatic memories prior to stimulation enhanced symptom reduction compared with stimulation alone.
This approach is grounded in the theory of memory, which posits that reactivated memories enter a transiently labile state during which their emotional intensity can be modified. Experimental and clinical studies have demonstrated that targeted interventions delivered during this window can weaken maladaptive emotional memories. In OCD, intrusive thoughts typically accompanied by fear, disgust, or distress may therefore constitute ideal targets for reconsolidation-based modulation.
Symptom provocation is widely used in neuroimaging research to activate OCD-related circuits and forms part of ERP-based treatment strategies. More recently, introduced its use before rTMS in OCD, reporting significant symptom reduction, although the specific contribution of provocation could not be isolated as all participants received it. Despite the fact that the specific contribution of symptom provocation could not be isolated in the initial trial, its continued use in clinical research has been supported by the excellent results reported in subsequent studies, as well as by its good acceptability among patients. The same research group recently published a standardized symptom-provocation protocol to ensure strong reproducibility and methodological reliability. This intervention requires only basic clinical skills and does not involve the use of complex psychotherapeutic techniques such as cognitive restructuring or symptom interpretation. To date, no study has evaluated symptom provocation combined with tDCS.
Given the safety, accessibility, and potential for home-based use of tDCS, identifying strategies that enhance its effectiveness is of clinical relevance. Brief activation of symptom-triggering cues prior to stimulation may allow tDCS to more effectively modulate targeted neural networks.
Objective This multicentre randomised controlled trial aims to determine whether personalised symptom provocation combined with bifocal tDCS (anodal right OFC, cathodal SMA) produces greater clinical improvement than tDCS alone in adults with severe, treatment-resistant OCD.
This study is a multicentre, randomised, controlled, single-blind clinical trial conducted across six french psychiatric centres in France (Poitiers, Nantes, Rennes, Limoges, Thouars and Angoulême). Eligible participants with severe, treatment-resistant OCD will be randomly allocated (1:1) to one of two parallel groups:
Centre Hospitalier Henri Laborit is the lead sponsor of 27 studies on the registry; 17 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Treatment-resistant OCD, defined as:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
DSM diagnostic criteria
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
These patients will only receive tDCS
Procedure: tDCS session
These patients will experience symptom provocation followed with tDCS
Procedure: tDCS session · Behavioral: symptom provocation
An active bifocal tDCS delivered through a CE-certified stimulator. The bifocal montage consists of an anodal electrode over the right orbitofrontal cortex (OFC) and a cathodal electrode over the supplementary motor area (SMA), with 5X5 cm electrod. Stimulation intensity is set at 2 mA, with a 30-minute session duration, including 30-second ramp-up and ramp-down periods.
A 3-5 minutes personalised symptom provocation procedure immediately before stimulation. This standardised clinical procedure induces brief activation of obsession-related distress without engaging in compulsions. It is delivered by a trained clinician health-care professional and does not constitute psychotherapeutic treatment.
Variation of Yale-Brown Obsessive-Compulsive Scale score
The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) is a clinician-administered assessment used to measure the severity of obsessive-compulsive disorder (OCD). Scores range from 0 to 40, with higher scores indicating more severe symptoms.
Time frame: measured at baseline and 42 days after the start of the therapy
Persistence of variation of Yale-Brown Obsessive-Compulsive Scale score and Obsessive-Compulsive Inventory-Revised
Assessment of the persistence of the therapeutic response at day 102 and 162 with the Y-BOCS and OCI-R scales. The Obsessive-Compulsive Inventory-Revised (OCI-R) is a self-report measure designed to assess the severity and type of obsessive-compulsive disorder (OCD) symptoms. It evaluates six symptom dimensions: washing, checking, ordering, hoarding, neutralizing, and obsessing. Each dimension is scored from 0 to 12, with higher scores indicating greater symptom severity.
Time frame: measured between baseline, day 102 / day 162
Comparison of Clinical Global Impression Improvement between both groups
The Clinical Global Impression (CGI) is a hetero-evaluation scale widely used in clinical studies to evaluate baseline severity and improvement in relation to treatment.
Time frame: Scales assessed at baseline, day 42, 102 and 162
Assessment of the Montgomery and Asberg Depression Rating Scale
The Montgomery and Asberg Depression Rating Scale (MADRS) is a hetero-evaluation rating scale used to assess the severity of depressive symptoms. It consists of 10 items evaluating core dimensions of depression. Total scores range from 0 to 60, with higher scores indicating more severe depression.
Time frame: Scales assessed at baseline, day 42, day 102, day 162
Assessment of 36-Item Short Form Health Survey
The 36-Item Short Form Health Survey (SF-36) is a self-assessed scale to measure 8 dimensions of health and quality of life. Each dimension is graded on a score of 0 to 100, 0 being the poorest estimate of quality of life and 100 being the best.
Time frame: baseline, day 102, and day 162
Analysis of side effects and tolerance of tDCS
Assessed with the Brunoni questionnaire
Time frame: Assessed during treatment
Analysis of complete response rate
35% improvement of the Y-BOCS score.
Time frame: between baseline and days 42 / day 102 / day 162
Assessment of the Hospital Anxiety and Depression scale
The Hospital Anxiety and Depression scale is a self-assessed scale yielding anxiety and depression scores ranging from 0 to 15 each (and a global score of 30), corresponding to higher depression or anxiety severities.
Time frame: baseline, day 42, day 102, day 162
Assessment of insight with the Brown Assessment of Beliefs Scale
The Brown Assessment of Beliefs scale is a clinician-assessed scale producing a score between 0 and 24. A higher score indicates a weaker insight.
Time frame: baseline, day 42, day 102, day 162
"Echelle d'évaluation Globale du Fonctionnement": Assessment of psychological and socio-professional functioning
The "Echelle d'évaluation Globale du Fonctionnement" (EGF) evaluates the psychological and socio-professional functioning. It is a clinican-graded scale giving a score of 1 - 100. A score of 100 corresponds to high functioning with absence of symptoms.
Time frame: baseline, day 102, day 162
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Compulsive Personality Disorder
Centre Hospitalier Henri Laborit