Transcranial Direct Current Stimulation Potentiation of Fear Extinction in OCD

Obsessive-Compulsive Disorder Clinical Trial

Official title:

Transcranial Direct Current Stimulation Potentiation of Fear Extinction in OCD: Towards Rational Design of Combination Therapies

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05521074
• Other study ID #: 2022P001065
• Status: Recruiting
• Phase: N/A
• Start date: September 15, 2022
• Est. completion date: March 2025

Study information

• Verified date: October 2023
• Source: Massachusetts General Hospital
• Contact: Peyton Miyares, BA
• Phone: 617-643-0850
• Email: mghocdfearstudy[@]partners.org
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The investigators want to learn more about how human beings learn not to fear and the impact of changing the fear network in the brain using transcranial Direct Current Stimulation (tDCS) in individuals with obsessive compulsive disorder (OCD). The investigators hope this study will help us understand how future treatments can help patients with OCD better control unwanted fear.

Description:

To address this question behaviorally and biologically, the investigators will use a, 2-day fear extinction paradigm while measuring behavioral psychophysiology (skin conductance response [SCR]) and neurophysiology (electroencephalography [EEG]). On Day 1 participants will undergo 1) habituation, 2) fear conditioning, and 3) extinction learning. On Day 2 they will undergo 4) extinction recall, and 5) reinstatement. SCR and EEG will be measured in both sessions. The investigators propose to investigate whether inhibitory tDCS to the pre-SMA before, during, or after fear extinction significantly 1) enhances the recall of extinction learning and 2) reduces fronto-medial theta power during extinction recall. Participants will be randomized to one of the following four conditions: active tDCS before, during, or after extinction learning, or sham tDCS. The fear extinction paradigm serves as a proxy of exposure-based CBT for OCD. Defining the combination protocol that optimally and significantly increases extinction recall behaviorally (psychophysiology) in OCD, will have critical implications for the mechanistically informed development of tDCS-augmented CBT for OCD. EEG measures will provide a response biomarker to characterize target engagement neurophysiologically. This is particularly relevant given EEG's ease of use, relatively low cost, and potential for greater translation to the clinic. Also, the higher signal-to-noise ratio (SNR) of EEG compared to SCR is a strength. Taken together, these data should reveal treatment targets, define optimal therapeutic protocols, and provide the foundation for a future clinical trial to test the synergistic efficacy of combined tDCS-CBT for OCD.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 120
• Est. completion date: March 2025
• Est. primary completion date: March 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• Fluent in English, willing to provide informed consent, and willing to comply with the study protocol

• Primary OCD that causes at least moderate distress and/or impairment (Y-BOCS total score = 16)

• Comfortable and capable of using a computer and completing computerized tasks

Exclusion Criteria:

• History of head injury resulting in prolonged (i.e., >1h) loss of consciousness and/or neurological sequelae; history of stroke; signs of increased intracranial pressure; prior neurosurgical procedure (e.g., DBS, aneurysm clips)

• Contraindications to participate in tDCS including: metallic implants in head or neck; ventriculoperitoneal (VP) shunts; pacemakers; pregnancy; epilepsy.

• Current or history of neurologic or psychiatric disease (e.g., mental retardation, dementia, brain damage, or other cognitive impairment) that would interfere with ability to participate in the study

• Impaired (or uncorrected) vision that would interfere with participation.

• Current clinically significant suicidality that requires psychiatric hospitalization, as indicated by clinical judgment.

• Current substance use disorder (within the past 12 months)

• Lifetime manic episode or psychosis

• Documented resistance to 4 or more valid pharmacological trials and previous treatment with =12 sessions of cognitive behavioral therapy for OCD with no response (or worsening symptoms)

• Use of most psychotropic medications (e.g., SSRIs and atypical antipsychotics) will be allowed. However, use of benzodiazepines within 2 weeks prior to the study is exclusionary (and participants will be asked to refrain from use of such medications during the study as they may interfere with the fear extinction paradigm).

• Unable to obtain low enough impedance values to ensure safe and effective application of tDCS/EEG.

Related Conditions & MeSH terms

• Obsessive-Compulsive Disorder

Intervention

Device:
• Active tDCS
The investigators will use commercially available tDCS equipment (Neuroelectrics©, Barcelona, Spain). The cathode will be placed over the pre-SMA using the 10-20 EEG system and the anode will be on the right deltoid.
• Sham tDCS
The investigators will use commercially available tDCS equipment (Neuroelectrics©, Barcelona, Spain). The cathode will be placed over the pre-SMA using the 10-20 EEG system and the anode will be on the right deltoid. tDCS will not be active in this condition.

Locations

Country	Name	City	State
United States	Massachusetts General Hospital	Boston	Massachusetts

Sponsors (2)

Lead Sponsor	Collaborator
Massachusetts General Hospital	Foundation for OCD Research

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Difference in skin conductance response (SCR) to the conditioned stimulus (CS+) versus the unconditioned stimulus (CS-) between tDCS conditions during extinction recall	Higher skin conductance (microSiemens) indicates greater fear intensity.	Extinction Recall Phase (Day 2)
Primary	Difference in frontomedial theta power (EEG) to the conditioned stimulus (CS+) versus the unconditioned stimulus (CS-) between tDCS conditions during extinction recall	Greater reduction of frontomedial theta power (microvolts) indicates stronger extinction recall.	Extinction Recall Phase (Day 2)

External Links

•   Eligibility Interest Form
•   Study website with more information