Home-based Transcranial Direct Current Stimulation (tDCS) for Treatment of Attention-deficit/Hyperactivity Disorder (ADHD)

Study Overview
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Brief Summary
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The investigators are investigating whether home-based tDCS over the course of four weeks can improve ADHD symptom severity and improve dysexecutive functioning (cognitive control). Further, the investigators are investigating whether there is a dose-dependent response to tDCS.

Detailed Description
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This mechanistic clinical trial will be the first of its kind to assess the clinical and cognitive efficacy of tDCS, and its relationship to physiological target engagement. It will also provide critical knowledge about tDCS dosing in a therapeutic context (i.e. 30 days of daily tDCS). Last, it will assess the feasibility and acceptability of home-based neuromodulation therapies for ADHD, reducing the most significant obstacle for the implementation of devices therapies (i.e. daily visits to the hospital for several weeks) and facilitating access to advanced therapeutics to a large population of patients with ADHD. An additional goal of the proposed study is to assess the feasibility and acceptability of home-based neuromodulation therapies for ADHD, reducing the most significant obstacle for the implementation of devices therapies (i.e. daily visits to the hospital for several weeks) and facilitating access to advanced therapeutics to a large population of patients with ADHD.

Official Title
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Home-based Transcranial Direct Current Stimulation (tDCS) for Treatment of Attention-deficit/Hyperactivity Disorder (ADHD)

Conditions
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Attention Deficit Disorder, Attention Deficit Disorder With Hyperactivity

Intervention / Treatment
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* Device: 2 mA transcranial direct current stimulation (tDCS)
* Device: 1 mA transcranial direct current stimulation (tDCS)
* Device: Sham transcranial direct current stimulation (tDCS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and female outpatients 18-65 years of age A diagnosis of ADD/ADHD or meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria. Exclusion Criteria: Contraindication to tDCS: history or epilepsy, metallic implants in the head and neck, brain stimulators, vagus nerve stimulators, VP shunt, pacemakers, pregnancy. Active substance dependence (except for tobacco). Pregnant or nursing females. Inability to participate in testing procedures. Premorbid neurological conditions (including neurovascular and neurodegenerative diseases such as traumatic brain injury, stroke, Parkinson's, AD and other dementias) and severe psychiatric disorders (bipolar disorder, schizophrenia).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Subjects will be randomized during the first study visit to the 2mA, 1mA, or sham conditions. Subjects will not change dose throughout study.
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 2mA transcranial direct current stimulation<br> | Device: 2 mA transcranial direct current stimulation (tDCS)<br>* tDCS is a non-invasive neuromodulatory technique that has previously demonstrated the ability to transiently modulate cognitive domains in both healthy and psychiatric populations. In the 2mA condition, the investigators will assist the administration of a 2mA current stimulation from the device.<br>|
| Experimental: 1mA transcranial direct current stimulation<br> | Device: 1 mA transcranial direct current stimulation (tDCS)<br>* tDCS is a non-invasive neuromodulatory technique that has previously demonstrated the ability to transiently modulate cognitive domains in both healthy and psychiatric populations. In the 1mA condition, the investigators will assist the administration of a 1mA current stimulation from the device.<br>|
| Sham Comparator: Sham transcranial direct current stimulation<br> | Device: Sham transcranial direct current stimulation (tDCS)<br>* tDCS is a non-invasive neuromodulatory technique that has previously demonstrated the ability to transiently modulate cognitive domains in both healthy and psychiatric populations. In the sham condition, the investigators will assist the administration of a sham stimulation from the device.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| P300 Amplitude during Erickson Flanker Task | P300, an electrophysiological feature theorized to represent executive functioning, has been previously shown to be notably diminished during the Erickson Flanker Task (EFT) . We will be administering this task to assess changes in P300 during the EFT, and if any changes are related to subjects' assigned condition. | Week 1 - Week 8 of Study | 
| Global Assessment of Functioning (GAF) Scale | investigators will use GAF scale to assess the potential feasibility of at-home tDCS for future research. | Week 1 - Week 8 of Study | 
| Adult ADHD Self-Report Scale | Investigators will assess changes to these questionnaires in reference to assigned stimulation group to assess changes to ADHD symptomatology across study duration. | Week 1 - Week 8 of Study |