Effect of Methylphenidate on Connectivity

Recruitment & Eligibility

Inclusion Criteria

Male sex
Written informed consent
For the Attention Deficit Hyperactivity Disorder group only: a diagnosis of Attention Deficit Hyperactivity Disorder

Exclusion Criteria

Age under 18 or > 40
Previous or current medical, psychiatric, or neurological problems (with exception of Attention Deficit Hyperactivity Disorder group)
Use of psychotropic medication
Use of recreational drugs in the two weeks before start of the study
Consuming an equivalent of > 5 cups of coffee per day
Consuming three or more alcohol units per day
The presence of one or more of the contraindications or warnings against the study drug as listed in the Summary of Product Characteristic
Presence of any contraindication to Magnetic Resonance Imaging scanning (e.g. implanted metallic object or electronic device)

Study & Design

Arm && Interventions

Group	Intervention	Description
Attention Deficit Hyperactivity Disorder	Placebo	Adult males with Attention Deficit Hyperactivity disorder will participate in a crossover design and receive both methylphenidate and placebo on two separate days.
Healthy adults	Methylphenidate	Healthy male adults will participate in a crossover design and receive both methylphenidate and placebo on two separate days.
Healthy adults	Placebo	Healthy male adults will participate in a crossover design and receive both methylphenidate and placebo on two separate days.
Attention Deficit Hyperactivity Disorder	Methylphenidate	Adult males with Attention Deficit Hyperactivity disorder will participate in a crossover design and receive both methylphenidate and placebo on two separate days.

Primary Outcome Measures

Name	Time	Method
The difference in functional connectivity as measured with functional Magnetic Resonance Imaging between participants who ingested methylphenidate and those who ingested placebo.	After the last patient has completed the last visit, which is expected to be two years after the start of the study	The primary objective in the current trial is to use graph theory to examine how the organization of the functional brain network may be altered by the administration of methylphenidate. The main question we intend to answer in this study, is whether, and if so to what extent, methylphenidate affects the organization of brain networks.

Secondary Outcome Measures

Name	Time	Method
The difference in functional connectivity as measured by functional Magnetic Resonance Imaging between participants with Attention Deficit Hyperactivity Disorder and healthy controls.	After the last patient has completed the last visit, which is expected to be two years after the start of the study	To examine if any of the effects on brain connectivity differ between participants with Attention Deficit Hyperactivity Disorder versus healthy controls.
The correlation of graph metrics (as a measure of functional network organization) with performance (scores) on cognitive tasks and blood levels of methylphenidate.	After the last patient has completed the last visit, which is expected to be two years after the start of the study	To examine how a reorganization of brain networks as described in the primary objective is related to improvements in cognitive performance and to blood levels of methylphenidate.
The correlation of whole brain cortical thickness and white matter volume as measured with Magnetic Resonance Imaging with both graph metrics as measured with functional Magnetic Resonance Imaging and scores on cognitive tests.	After the last patient has completed the last visit, which is expected to be two years after the start of the study	To examine if certain network structures of the brain, such as cortical thickness and white matter volume, are related to susceptibility to medication efficacy and if the structural qualities are related to cognitive performance.

Recruitment & Eligibility