Transcranial Direct Current Stimulation (tDCS) in Pediatric Obsessive Compulsive Disorder (OCD)

Study Overview
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Brief Summary
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In this study, the investigators aim to understand the role of transcranial direct current stimulation (tDCS) in modulating aberrant neurocognitive processes implicated in pediatric patients with obsessive compulsive disorder (OCD).

Detailed Description
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In this study, the investigators aim to understand the role of transcranial direct current stimulation (tDCS) in modulating aberrant neurocognitive processes implicated in pediatric patients with obsessive compulsive disorder (OCD). The investigators propose two arms of the study that will investigate fear extinction learning and inhibitory control in one arm (A), and goal orientated versus habit-based behavior and inhibitory control in the other (B). All subjects will undergo three study conditions: two with active tDCS to each of two different brain targets and one under sham tDCS. The order of stimulation (sham or active tDCS) will be randomized.

Official Title
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Transcranial Direct Current Stimulation (tDCS) Modulation of Neurocognitive Processes Underlying Pediatric Obsessive Compulsive Disorder (OCD)

Conditions
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Obsessive-Compulsive Disorder, Pediatric Psychiatric Disorder

Intervention / Treatment
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* Device: Transcranial Direct Current Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Outpatient youth between the ages 10-17 years Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) ≥16 (moderately severe). OCD must be determined to be the primary or co-primary diagnosis using the The Schedule for Affective Disorders and Schizophrenia for School-Age Children- Computer administered version (KSADS-COMP) based on all available information. Child has a full-scale IQ≥85 as assessed on the Wechsler Abbreviated Scale of Intelligence® Second Edition (WASI®-II) (within 90% CI). To decrease participant burden, the WASI®-II will only be conducted in cases of suspected intellectual disability after meeting with the PI. English speaking. Exclusion Criteria: Receiving concurrent psychotherapy for subject's OCD (except maintenance).Subjects receiving pre- established concurrent psychotherapy for at least 8 weeks regarding other psychological issues are eligible for enrollment. New Treatments: Initiation of an antidepressant within 12 weeks before study enrollment or an antipsychotic 6 weeks before study enrollment. No new alternative medications, nutritional or therapeutic diets within 6 weeks of study enrolment. Established Treatment changes: Any change in established psychotropic medication (e.g., antidepressants, anxiolytics, stimulant, alpha agonist) within 8 weeks before study enrollment (6 weeks for antipsychotic). Alternative medications must be stable for 6 weeks prior to baseline. Any medications must remain stable during treatment; consistent with the National Institute of Health (NIH)-funded Child Anxiety Multimodal Study (CAMS) trial, downward adjustments due to side effects may be acceptable and will be discussed with the study child and adolescent psychiatrist and the community psychiatrist. Current clinically significant suicidality or individuals who have engaged in suicidal behaviors within 6 months will be excluded and referred for appropriate clinical care. Meets Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) criteria for conduct disorder, autism, bipolar, attention deficit hyperactivity disorder (ADHD), Tourette's syndrome, schizophrenia or schizoaffective disorders Youth with hoarding symptoms as they may be conceptually and genetically different from other OCD subtypes. BMI less than 18.5. Contraindication to tDCS: history or epilepsy, metallic implants in the head and neck, brain stimulators, vagus nerve stimulators, ventriculoperitoneal (VP) shunt, pacemakers. Active substance dependence (except for tobacco). Pregnant or nursing females as the effects of tDCS on pregnancy are unknown. Presence of a significant and/or unstable medical illness that might lead to hospitalization during the study.

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Inhibitory Control/ Fear Extinction<br>This arm will investigate the effect of tDCS on tasks assessing Inhibitory Control/ Fear Extinction. This group will undergo three sessions of tDCS: two active sessions and one sham session. The order of the sessions is randomized. | Device: Transcranial Direct Current Stimulation<br>* In tDCS, electrodes are applied on the scalp to transmit direct current at low current amplitudes.<br>* Other names: tDCS;|
| Experimental: Inhibitory Control/ Goal-Orientated vs Habit-Based Behavior<br>This arm will investigate the effect of tDCS on tasks assessing Inhibitory Control/ Goal-Orientated versus Habit-Based Behavior. This group will undergo three sessions of tDCS: two active sessions and one sham session. The order of the sessions is randomized. | Device: Transcranial Direct Current Stimulation<br>* In tDCS, electrodes are applied on the scalp to transmit direct current at low current amplitudes.<br>* Other names: tDCS;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Stop Signal Task | Ability to Inhibit a Response Task | 50 minutes- 20 minutes before and immediately after a single 30 minute tDCS session | 
| Change in Fear Extinction Recall Task | Degree of recall to a previously extinguished conditioned stimulus | Within 12-24 hours after the tDCS session the day before | 
| Change in Sequential Spaceship Task | Ability to increase the proportion of Goal-Orientated versus Habit-Based Behaviour | 40 minutes- immediately before and 10 minutes after a 30 minute single tDCS session | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in EEG readings | Degree and type of change in event related potentials (ERPs) amplitudes | 90 minutes- 30 minutes before and 30 minutes after a single 30 minute tDCS session | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcranial Direct Current Stimulation