Motivated Behavior in Adults With and Without ADHD

Study Overview
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Brief Summary
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To investigate the effects of methylphenidate on motivated behavior in adults with and without ADHD

Detailed Description
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This study has a mixed between- and within-subject design. Participants are young adults (aged 18-45) with ADHD and non-ADHD matched controls. They will be recruited from locations around the community, consented, screened for eligibility, then scheduled for 2 study days. Study days will be at least 48 hours apart. Thus, there will be a total of 3 lab visits across a 3 week period. Participants will be administered study drug on one study day and placebo on the other study day. They will complete a battery of cognitive/behavioral tasks and answer questionnaires on both study days.

Official Title
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Motivated Behavior in Adults With and Without ADHD

Conditions
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ADHD

Intervention / Treatment
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* Drug: ADHD methylphenidate first, placebo second
* Drug: ADHD placebo first, methylphenidate second
* Drug: Non-ADHD methylphenidate first, placebo second
* Drug: Non-ADHD placebo first, methylphenidate second


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: generally healthy between the ages of 18-45 non-ADHD subjects do not meet criteria for ADHD diagnosis or any subtype as determined by the Conners Diagnostic Interview or any T-Score > 55 on Inattentive Symptoms, Hyperactive-Impulsive Symptoms, Total Symptoms or ADHD Index subscales of the CAARS. ADHD subjects meet criteria for a primary diagnosis of ADHD, any subtype, based on DSM-5 Exclusion Criteria: inability to attend all required experimental sessions significant health problems (e.g., current and uncontrolled liver, lung, or heart problems, current or past seizure disorder, serious head trauma) primary diagnosis of Axis I psychiatric disorders other than ADHD (e.g., depression, anxiety disorder, schizophrenia) meet DSM-5 criteria for substance use disorder other than nicotine in the past 12 months use of psychoactive medications in the past 6 months as indicated by self-report positive urine drug screen for drugs or positive breath alcohol concentration contraindications for MPH among women, nursing or a positive pregnancy test IQ < 80 on Kaufman Brief Intelligence Test, 2nd edition allergy to lactose hypertension (If subject is ≤ 40 years of age and has blood pressure over 135/85 or heart rate over 90 beats per minute. If subject is > 40 years of age and has blood pressure over 130/80 or heart rate over 88 beats per minute) body mass ratio > 30

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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: Non-Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: There are two parallel arms of this study (ADHD or non-ADHD subjects). Within each arm, each subject will be exposed to placebo and a drug (each at a different timepoint in the study). Although all subjects will receive both placebo and the drug, the order of presentation of the placebo and drug is counterbalanced across subjects (i.e., approximately half will receive the drug first and approximately half will receive the placebo first). For both study arms, regardless of whether the placebo is received first or second, the outcome measure will be calculated as the number of high effort selections.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ADHD group<br>Adults with ADHD | Drug: ADHD methylphenidate first, placebo second<br>* double-blind, counter-balanced administration<br>Drug: ADHD placebo first, methylphenidate second<br>* double-blind, counter-balanced administration<br>|
| Experimental: non-ADHD group<br>Adults without ADHD | Drug: Non-ADHD methylphenidate first, placebo second<br>* double-blind, counter-balanced administration<br>Drug: Non-ADHD placebo first, methylphenidate second<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of High-effort Selections in the Effort-based Decision Making Task | Number of high-effort selections in the effort-based decision making task from the placebo to the methylphenidate condition. This is a decision-making task where participants make high- or low-effort choices to earn a small financial reward. High-effort selections require 100 button presses with non-dominant hand pinky finger and low-effort selections require 30 button presses with dominant hand index finger (within 15 seconds). The number of high effort selections are summed across 50 trials of the task. This task measures the willingness to perform effort in relation to changing reward magnitude and probability. This is a basic science experiment, the clinical and/or physiological relevance of these results are not established. | 1 hour post drug (or placebo) administration for each study session |