Multimodal Brain Imaging of the Neural Effects of Methylphenidate in Patients With ADHD

Study Overview
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Brief Summary
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The investigators' goal is to develop neuroimaging biomarkers to predict response to treatment with methylphenidate, which then can be used in the development of novel pharmacological treatments for attention-deficit/hyperactivity disorder (ADHD). The overall objective of this study is to measure the changes in task-related neural activity related to symptoms of ADHD (measured by functional MRI) and brain glutamate levels (measured by magnetic resonance spectroscopy, MRS) after treatment with methylphenidate (MPH). This will be a double-blind crossover of methylphenidate and placebo in adults with ADHD. Participants will complete neuropsychological testing along with fMRI and MRS scans after a single dose of each treatment.

Official Title
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Multimodal Brain Imaging of the Neural Effects of Methylphenidate in Patients With ADHD

Conditions
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ADHD - Combined Type

Intervention / Treatment
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* Drug: Methylphenidate
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: right handed Exclusion Criteria: pregnant or breast feeding past or current neurological disorder non-ADHD cause of cognitive impairment uncontrolled medical disorder head trauma with loss of consciousness in the last year or any evidence of functional impairment due to and persisting after head trauma having an adverse reaction to methylphenidate, or other stimulant medication having a contraindication to MRI current smoking

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 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
Interventional Model Description: This is a double-blind cross over of a single dose of methylphenidate (10mg or 15mg) and matching placebo.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Methylphenidate first<br>Single oral dose of methylphenidate (10mg or 15 mg) and then matching placebo after washout period of one week. | Drug: Methylphenidate<br>* single dose of 10 mg or 15 mg<br>Drug: Placebo<br>* Matching placebo<br>|
| Placebo Comparator: Placebo first<br>Matching placebo and then single oral dose of methylphenidate (10mg or 15 mg) after washout period of one week. | Drug: Methylphenidate<br>* single dose of 10 mg or 15 mg<br>Drug: Placebo<br>* Matching placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BOLD signal during response inhibition | BOLD signal (brain activity during fMRI, arbitrary units) in the anterior cingulate cortex during response inhibition. | Approximately 90 minutes after dose | 
| Glutamate level in the anterior cingulate cortex | Glutamate level (measured by MRS, institutional units) in the anterior cingulate cortex. | Approximately 2 hours after dose |