Dopaminergic Modulation of Cognition and Psychomotor Function

A recent study at our lab showed increased episodic memory consolidation and response readiness after treatment with methylphenidate in healthy volunteers. The investigators seek to replicate and extend these findings. Furthermore the pharmacological specificity of these effects will be studied. Since methylphenidate has an effect on two neurotransmitters, dopamine and noradrenaline, either could be responsible for the observed effects. In order to explore the dopaminergic contribution to this effect, the study proposed here includes not only methylphenidate but also levodopa/carbidopa, which only affects dopamine and not noradrenaline.

In this study, 20 healthy males and females between 18 and 45 years of age will participate. They will be recruited via advertisements at Maastricht University and in local newspapers.

Participants will be treated once with methylphenidate, once with levodopa/carbidopa and once with placebo. All medications will be administered orally with a capsule.

It is hypothesized that methylphenidate and levodopa/carbidopa will both enhance episodic memory consolidation and improve response readiness

Study Overview

• Status: Completed
• Conditions: Dopamine Activity; Episodic Memory Consolidation; Response Preparation
• Intervention / Treatment: Drug: Methylphenidate 40 mg; Drug: Levodopa/carbidopa 125 mg; Drug: Domperidon 10 mg

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Limburg
    • Maastricht, Limburg, Netherlands, 6200
      • Maastricht University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Male or female
• 18 to 45 years of age
• Healthy (i.e. absence of all exclusion criteria), normal static binocular acuity (corrected or uncorrected),
• Body mass index between 18.5 and 30
• Willingness to sign an informed consent.

Exclusion Criteria:

• history of cardiac, hepatic, renal, pulmonary, neurological, gastrointestinal, haematological or psychiatric illness.
• history of depression, bipolar disorder, anxiety disorder, panic disorder, psychosis, or attention deficit hyperactivity disorder will be excluded from participation.
• first-degree relative with a psychiatric disorder or a history with a psychiatric disorder
• excessive drinking (>20 glasses of alcohol containing beverages a week
• pregnancy or lactation
• use of medication other than oral contraceptives
• use of recreational drugs from 2 weeks before until the end of the experiment
• any condition in which gastrointestinal motility might carry any risk
• any sensory or motor deficits which could reasonably be expected to affect test performance

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: DOUBLE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Medication; In this study, a crossover design is applied. All participants receive all three treatments in randomized order on separate days.	Drug: Methylphenidate 40 mg; Oral dose 40 mg; Other Names: Ritalin RVG 03957; Drug: Levodopa/carbidopa 125 mg; oral dose, 100 mg levodopa, 25 mg carbidopa in one capsule; Other Names: Sinemet RVG08740; Drug: Domperidon 10 mg; Domperidon 10 mg; Other Names: Domperidon RVG 23565

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Behavioral score on the Word learning test	Number of words recalled in the word learning test	1 day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CNV amplitude	Amplitude of the CNV wave in the EEG	1 day
Reaction time on the CNV	Reaction time in the response preparation task in which CNV is measured	1 day

Collaborators and Investigators

• Sponsor: Maastricht University Medical Center
• Investigators: Principal Investigator: Eric Vuurman, Dr., Dept Neuropsychology and Psychopharmacology, Maastricht University

Study record dates

Study Major Dates

• Study Start: November 1, 2010
• Primary Completion (ACTUAL): June 1, 2012
• Study Completion (ACTUAL): June 1, 2012

Study Registration Dates

• First Submitted: September 22, 2010
• First Submitted That Met QC Criteria: October 7, 2010
• First Posted (ESTIMATE): October 11, 2010

Study Record Updates

• Last Update Posted (ESTIMATE): October 25, 2012
• Last Update Submitted That Met QC Criteria: October 24, 2012
• Last Verified: October 1, 2012

More Information

Terms related to this study

• Keywords: levodopa; EEG; dopamine; methylphenidate; episodic memory; contingent negative variation; response preparation
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Enzyme Inhibitors; Antiemetics; Gastrointestinal Agents; Neurotransmitter Uptake Inhibitors; Membrane Transport Modulators; Dopamine Agents; Dopamine Antagonists; Dopamine Uptake Inhibitors; Central Nervous System Stimulants; Antiparkinson Agents; Anti-Dyskinesia Agents; Aromatic Amino Acid Decarboxylase Inhibitors; Methylphenidate; Levodopa; Domperidone; Carbidopa
• Other Study ID Numbers: 10-3-056