Effects of Modafinil, Caffeine and Methylphenidate in Healthy Volunteers

Study Overview
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Brief Summary
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In this study the investigators compare three stimulants to each other. The effects of these agents on cognitive performance (eg, attention and memory) and on the brain are being measured. The hypothesis is that stimulants will have a positive effect on cognitive performance. Each study participant will receive once a placebo and once methylphenidate or modafinil or caffeine. Methylphenidate (also known as Ritalin ®) is a drug that is used in the treatment of attention deficit / hyperactivity disorder (ADHD) in children, adolescents and adults. Modafinil ( Vigil ®) is a drug used in the treatment of narcolepsy (sleeping sickness). In the study. These substances are given in the study only once and in the dosages in which is also used for the treatment of the above diseases. In the case of caffeine , the dosage corresponds to two cups of coffee.

Official Title
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Effects of Modafinil, Caffeine and Methylphenidate on Functional Brain Activity and Cognitive Performance in Healthy Volunteers: a Randomized, Placebo-controlled, Double-blind fMRI Study

Conditions
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Healthy

Intervention / Treatment
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* Drug: Methylphenidate 20 mg tablet given once by mouth
* Drug: modafinil 200mg tablet given once by mouth
* Drug: caffein 200mg tablet given once by mouth
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men 18 - 35 years Written consent (according to Arzneimittelgesetz (AMG) § 40 (1) 3b) Good knowledge of German Right-handedness Exclusion Criteria: Known hypersensitivity to the study medication All contraindications to the study medication: arrhythmia, hyperthyroidism , glaucoma , pheochromocytoma , congestive heart failure , diabetes mellitus, known liver and kidney dysfunction, vascular disease , angina, haemodynamically significant congenital heart disease , cardiomyopathy , myocardial infarction, channelopathies, arterial hypertension , cerebrovascular diseases , such as cerebral aneurysm , vascular abnormalities , including vasculitis and stroke. Participation in other clinical trials during or within one month prior to this clinical trial Medical or psychological circumstances that may endanger the proper conduct of the trial Existing serious somatic diseases, even if they are not covered by the contraindications according to product information Existing psychiatric disorders and psychiatric disorders in prehistory Smoker or ex-smoker for less than 5 years Regular caffeine consumption > 4 cups per day Subjects with irregular day -night rhythm (eg shift workers ) Unwillingness to the storage and disclosure of pseudonymous data as part of the clinical trial Accommodation in an institution by court or administrative order (according to AMG § 40 (1) 4 ) MRI contraindications ( eg pacemakers , metallic or electronic implants , metallic splinters , tinnitus, surgical clips )

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Male

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: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Methylphenidate and placebo<br>Placebo or Methylphenidate 20 mg tablet given once by mouth | Drug: Methylphenidate 20 mg tablet given once by mouth<br>* 3-arm, single-drug dosage comparison study<br>* Other names: Ritalin;Drug: placebo<br> <br> |
| Experimental: modafinil and placebo<br>placebo or modafinil 200mg tablet given once by mouth | Drug: modafinil 200mg tablet given once by mouth<br>* 3-arm, single-drug dosage comparison study<br>* Other names: Provigil;Drug: placebo<br> <br> |
| Experimental: caffein and placebo<br>placebo or caffein 200mg tablet given once by mouth | Drug: caffein 200mg tablet given once by mouth<br>* 3-arm, single-drug dosage comparison study<br>* Other names: Coffeinum;Drug: placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting state parameters of functional magnetic resonance imaging (fMRI) as a measure of brain activity | The resting state parameters that will be measured are regional homogeneity (ReHo) und amplitude of low frequency fluctuation (ALFF) | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Performance on cognitive tests | A test battery covering several cognitive domaines is being used including: digit-span-Task, dual n-back, psychomotor vigilance task, reasoning task, memory task (free recall/ recognition), mental speed task. | 4 hours | 
| Number of Participants with Adverse Events as a Measure of Safety and Tolerability |  | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Brain Activity