Modulating Prefrontal Circuits Underlying Behavioral Flexibility in OCD: A TMS Study

Study Overview
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Brief Summary
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This study investigates whether slow-frequency repetitive transcranial magnetic stimulation targeting frontal pole can acutely modulate brain circuits which show abnormal functioning during behavioral flexibility in obsessive-compulsive disorder, as well as performance on a behavioral task.

Official Title
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Modulating Prefrontal Circuits Underlying Behavioral Flexibility in OCD: A TMS Study

Conditions
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Obsessive-Compulsive Disorder

Intervention / Treatment
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* Device: rTMS
* Device: sham rTMS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: OCD group current primary diagnosis of obsessive-compulsive disorder and Yale-Brown Obsessive Compulsive Scale total score ≥ 16; 18-55 years of age; ability to speak, read, write, and understand English sufficiently well to complete study procedures and provide informed consent; either no use of psychiatric medication or stable psychiatric medication use for 6 weeks prior to study entry, limited to use of serotonin reuptake inhibitors and PRN use of benzodiazepines (other psychiatric medication use excluded), and right-handed. Inclusion Criteria: Healthy Control group 18-55 years of age; ability to speak, read, write, and understand English sufficiently well to complete study procedures and provide informed consent; right-handed. Exclusion Criteria: OCD group active problematic substance use; lifetime psychosis or bipolar mood disorder or OCD beliefs of delusional nature; clinically significant hoarding symptoms; active suicidal or homicidal ideation; significant neurological disease or intracranial pathology; use of medications which increase risk for seizures during TMS; significant or unstable medical disorders or contraindication to TMS or MRI scan. Exclusion Criteria: Healthy Control group current psychiatric diagnosis; lifetime psychosis, bipolar mood disorder, or OCD; active suicidal or homicidal ideation; significant neurological disease or intracranial pathology; use of psychiatric medications; use of medications which increase risk for seizures during TMS; significant or unstable medical disorders or contraindication to TMS or MRI scan.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: OCD, Active TMS<br>Participants with OCD who receive active rTMS | Device: rTMS<br>* 1-Hz rTMS targeting frontal pole<br>|
| Sham Comparator: OCD, Sham TMS<br>Participants with OCD who receive sham rTMS | Device: sham rTMS<br>* sham rTMS targeting frontal pole<br>|
| Other: Healthy Control, Active TMS<br>Healthy control participants who receive active rTMS | Device: rTMS<br>* 1-Hz rTMS targeting frontal pole<br>|
| Other: Healthy Control, Sham TMS<br>Healthy control participants who receive sham rTMS | Device: sham rTMS<br>* sham rTMS targeting frontal pole<br>|
| Other: Healthy Control, Active TMS (1 session)<br>Healthy control participants who receive 1 session of active, open-label rTMS | Device: rTMS<br>* 1-Hz rTMS targeting frontal pole<br>|
| Other: Healthy Control, Active TMS (3 sessions)<br>Healthy control participants who receive 3 sessions of active, open-label rTMS | Device: rTMS<br>* 1-Hz rTMS targeting frontal pole<br>|
| Other: OCD, Active TMS (3 session)<br>Participants with OCD who receive 3 sessions of active, open-label rTMS | Device: rTMS<br>* 1-Hz rTMS targeting frontal pole<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting-state functional connectivity with ventral striatum | Resting-state functional connectivity with ventral striatum (assessed via fMRI) | Before rTMS and approximately 1 day following open-label rTMS | 
| Resting-state functional connectivity with dorsal striatum | Resting-state functional connectivity with dorsal striatum (assessed via fMRI) | Before rTMS and approximately 1 day following open-label rTMS | 
| Cognitive flexibility task performance | Behavioral performance on a cognitive flexibility task (% trials correct) | Before rTMS and approximately 1 day following open-label rTMS |