NCT06834217 · Yale University
Transcranial Direct Current Stimulation and Extinction in Obsessive Compulsive Disorder
What this study is about
Obsessive-compulsive disorder (OCD) is associated with substantial impairments in quality of life and is among the most disabling psychiatric disorders. Exposure therapy is among the first-line of treatments for obsessive-compulsive disorder (OCD) . Extinction learning is thought to be a core mechanism of therapeutic exposure.
View original scientific description
Obsessive-compulsive disorder (OCD) is associated with substantial impairments in quality of life and is among the most disabling psychiatric disorders. Exposure therapy is among the first-line of treatments for obsessive-compulsive disorder (OCD) . Extinction learning is thought to be a core mechanism of therapeutic exposure. Fear and safety signal learning are traditionally associated with activity and connectivity within the canonical corticolimbic "fear circuit", which includes the amygdala, medial prefrontal cortex (mPFC), and hippocampus. Transcranial direct current stimulation (tDCS) is a neuromodulation technology that can augment brain plasticity, learning, and memory. The proposed study will test if obsessive-compulsive disorder (OCD) is associated with inhibitory safety learning deficits and if transcranial direct current stimulation (tDCS) normalizes functional connectivity and safety signal processing to recover extinction deficits in obsessive-compulsive disorder (OCD).
Interventions
DEVICE
Active transcranial direct current stimulation
Multifocal transcranial direct current stimulation will be delivered. The anode will be placed over the frontal pole (Fpz, 10-20 electroencephalogram \[EEG\]) and will be surrounded by 5 return electrodes (cathodes). Current will be set at 1.5mA and will be ramped in and out for 30 seconds at the beginning and end of a 20-minute stimulation period.
DEVICE
Sham transcranial direct current stimulation
Multifocal transcranial direct current stimulation will be delivered. The anode will be placed over the frontal pole (Fpz, 10-20 electroencephalogram \[EEG\]) and will be surrounded by 5 return electrodes (cathodes). Current will be set at 1.5mA and will be ramped in and out for 30 seconds at the beginning of a 20-minute period.
Primary outcome measures
Blood oxygen level-dependent (BOLD) response to create functional brain activation maps
Time frame: Blood oxygen level-dependent (BOLD) will be measured across 3 daily scan sessions separated by ~24 hours each; data will be reported from all 3 sessions.
Brain activity will be estimated with blood oxygen level-dependent (BOLD) response, which will be measured with magnetic resonance imaging (MRI).
Skin conductance response (SCR) will be measured by collecting electrodermal activity data from the left hand
Time frame: Skin conductance will be measured across all 3 scan sessions, separated by ~24 hours each; data will be reported from all 3 sessions.
Skin conductance data will be used as an index of anxious reactivity to experimental cues.
Threat expectancies will be measured by asking participants to rate the probability of receiving a shock using a 0-100 scale with zero equal to 0% chance and 100 equal to 100% chance; higher values are indicative of worse anxious reactivity
Time frame: Threat expectancies will be assessed at the beginning and end of each of the 3 scan session, separated by ~24-hours each; data will be reported from all 3 sessions.
Threat expectancies will be used as an index of anxious reactivity to experimental cues.
Functional brain connectivity will be measured blood oxygen level dependent (BOLD) response
Time frame: Resting functional connectivity will be measured at baseline during first scan session and during transcranial direct current stimulation in the second scan session; scan sessions will be separated by ~24 hours; data from both sessions will be reported.
Correlations in brain activity between regions and networks measured with blood oxygen level dependent (BOLD) response captured with magnetic resonance imaging (MRI)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- All Participant Inclusion Criteria would include:
- 18 years of age or older
- speak English fluently, and
- able to provide written and verbal informed consent.
- Obsessive-compulsive disorder (OCD) Inclusion Criteria would include:
- meet criteria for OCD as determined by structured clinical interview
- exhibit significant current symptoms of OCD
- report duration of OCD symptoms of at least 1-year
- OCD symptoms are primary or co-primary relative to other psychiatric diagnoses
- stable psychiatric treatment (≥8-weeks) or no active treatment.
- exhibit significant current symptoms of OCD as determined by the Dimensional Obsessive-Compulsive Scale (DOCS) (≥18).
Exclusion criteria
- All Participant Exclusion Criteria would include:
- active severe substance use disorder(s)
- acute suicidality
- history of bipolar or psychotic disorder(s)
- significant developmental disabilities
- loss of consciousness \> 10 minutes
- history of traumatic brain injury
- major neurological disease
- a positive pregnancy test
- other brain stimulation or magnetic resonance imaging contraindications
- new psychological treatment within the past 8 weeks
- daily anxiolytic medication use (e.g., benzodiazepine).
- Non-Clinical Control Exclusion Criteria would include:
- meet current criteria for a psychiatric disorder as determined by structured clinical interview
- active-psychotropic medications.
Where
- New Haven, Connecticut
Collaborators
National Institute of Mental Health (NIMH)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 23, 2026 · Source of record for eligibility and locations