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Psychology

D-Index
38
Citations
5188
World Ranking
8936
National Ranking
390

Overview

Eef L. Theunissen is affiliated with Maastricht University in the Netherlands and has developed a research profile centered on neuroscience, medicine, and psychology. Their work predominantly addresses the pharmacological and behavioral effects of psychoactive substances, drug tolerance, and neurochemical mechanisms influencing cognition and mood.

Theunissen has contributed extensively to the study of psychedelics and drug research, with a particular focus on neurotransmitter receptor influence on behavior and cannabis-related investigations. Their research topics also encompass forensic toxicology, chemical synthesis of alkaloids, and neuropharmacology. This interdisciplinary approach integrates clinical psychology, pharmacology, cellular and molecular neuroscience, toxicology, and organic chemistry.

Their frequent coauthors include Johannes G. Ramaekers, Natasha L. Mason, Kim P. C. Kuypers, Stefan W. Toennes, and Nadia R. P. W. Hutten, reflecting collaborative efforts spanning various aspects of psychopharmacology and neuroscience.

Key recent publications illustrate the scope and focus of Theunissen's research:

  • Effect of Cannabidiol and Δ9-Tetrahydrocannabinol on Driving Performance, 2020, JAMA
  • Low Doses of LSD Acutely Increase BDNF Blood Plasma Levels in Healthy Volunteers, 2020, ACS Pharmacology & Translational Science
  • Mood and cognition after administration of low LSD doses in healthy volunteers: A placebo controlled dose-effect finding study, 2020, European Neuropsychopharmacology
  • A low dose of lysergic acid diethylamide decreases pain perception in healthy volunteers, 2020, Journal of Psychopharmacology
  • Blunted highs: Pharmacodynamic and behavioral models of cannabis tolerance, 2020, European Neuropsychopharmacology

Theunissen regularly publishes in venues that are central to the fields of psychopharmacology and neuroscience. Prominent journals include European Neuropsychopharmacology, Psychopharmacology, Frontiers in Psychiatry, bioRxiv (Cold Spring Harbor Laboratory), and Nature Reviews. Neuroscience.

The main areas of study supporting their research output include:

  • Neuroscience
  • Medicine
  • Psychology

At the subfield level, their work spans:

  • Clinical Psychology
  • Pharmacology
  • Cellular and Molecular Neuroscience
  • Toxicology
  • Organic Chemistry

The primary topics addressed in Theunissen's publications cover:

  • Psychedelics and Drug Studies
  • Neurotransmitter Receptor Influence on Behavior
  • Cannabis and Cannabinoid Research
  • Forensic Toxicology and Drug Analysis
  • Chemical Synthesis and Alkaloids
  • Neuroscience and Neuropharmacology Research
  • Alkaloids: synthesis and pharmacology

Best Publications

  • High-Potency Marijuana Impairs Executive Function and Inhibitory Motor Control

    Johannes G Ramaekers;Gerhold Kauert;Peter van Ruitenbeek;Eef L Theunissen

  • Neurocognitive performance during acute THC intoxication in heavy and occasional cannabis users

    Johannes Gerardus Ramaekers;G. Kauert;E. Theunissen;Stefan W. Toennes

  • Cognition and motor control as a function of Delta9-THC concentration in serum and oral fluid: limits of impairment.

    J.G. Ramaekers;M.R. Moeller;P. van Ruitenbeek;E.L. Theunissen

  • Ayahuasca enhances creative divergent thinking while decreasing conventional convergent thinking

    Kim Kuypers;J Riba;M de la Fuente Revenga;S Barker

  • Tolerance and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis users

    Johannes Gerardus Ramaekers;Eef L. Theunissen;Marjolein de Brouwer;Stefan W. Toennes

  • Effect of Cannabidiol and Δ9-Tetrahydrocannabinol on Driving Performance: A Randomized Clinical Trial.

    Thomas R Arkell;Frederick Vinckenbosch;Richard C Kevin;Eef L Theunissen

  • Medicinal Δ(9) -tetrahydrocannabinol (dronabinol) impairs on-the-road driving performance of occasional and heavy cannabis users but is not detected in Standard Field Sobriety Tests.

    Wendy M Bosker;Kim P C Kuypers;Eef L Theunissen;Anke Surinx

  • Effects of acute MDMA intoxication on mood and impulsivity: role of the 5-HT2 and 5-HT1 receptors.

    Janelle H. P. van Wel;Kim P. C. Kuypers;Eef L. Theunissen;Wendy M. Bosker

  • Comparison of cannabinoid pharmacokinetic properties in occasional and heavy users smoking a marijuana or placebo joint

    Stefan W. Toennes;Johannes G. Ramaekers;Eef L. Theunissen;Manfred R. Moeller

  • Low Doses of LSD Acutely Increase BDNF Blood Plasma Levels in Healthy Volunteers.

    Nadia R. P. W. Hutten;Natasha L. Mason;Patrick C. Dolder;Eef L. Theunissen

  • Neurophysiological functioning of occasional and heavy cannabis users during THC intoxication.

    Eef L. Theunissen;Gerold F. Kauert;Stefan W. Toennes;Manfred R. Moeller

  • Mood and cognition after administration of low LSD doses in healthy volunteers: A placebo controlled dose-effect finding study

    Nadia R.P.W. Hutten;Natasha L. Mason;Patrick C. Dolder;Eef L. Theunissen

  • A placebo-controlled study to assess Standardized Field Sobriety Tests performance during alcohol and cannabis intoxication in heavy cannabis users and accuracy of point of collection testing devices for detecting THC in oral fluid.

    W. M. Bosker;E. L. Theunissen;S. Conen;K. P. C. Kuypers

  • Psychomotor function in chronic daily Cannabis smokers during sustained abstinence.

    Wendy M. Bosker;Erin L. Karschner;Dayong Lee;Robert S. Goodwin

  • Pharmacokinetic properties of the synthetic cannabinoid JWH-018 and of its metabolites in serum after inhalation

    Stefan W. Toennes;Anna Geraths;Werner Pogoda;Alexander Paulke

  • Cannabis and tolerance : acute drug impairment as a function of cannabis use history

    J. G. Ramaekers;J. H. van Wel;D. B. Spronk;S. W. Toennes

  • Pharmacokinetic properties of delta9-tetrahydrocannabinol in oral fluid of occasional and chronic users.

    Stefan W. Toennes;Johannes Gerardus Ramaekers;Eef L. Theunissen;Manfred R. Moeller

  • A low dose of lysergic acid diethylamide decreases pain perception in healthy volunteers

    Johannes G Ramaekers;Nadia Hutten;Natasha L Mason;Patrick Dolder

  • A randomized trial on the acute and steady-state effects of a new antidepressant, vortioxetine (Lu AA21004), on actual driving and cognition

    E. L. Theunissen;D. Street;A-m Højer;A. Vermeeren

  • Acute and subchronic effects of bilastine (20 and 40 mg) and hydroxyzine (50 mg) on actual driving performance in healthy volunteers

    Silke Conen;Eef L. Theunissen;Anita C. M. Van Oers;Román Valiente

  • Lack of effects between rupatadine 10 mg and placebo on actual driving performance of healthy volunteers

    Eric Vuurman;Eef Theunissen;Anita van Oers;Cees van Leeuwen

  • Residual effects of esmirtazapine on actual driving performance: overall findings and an exploratory analysis into the role of CYP2D6 phenotype

    Johannes Gerardus Ramaekers;Silke Conen;Pieter Jan de Kam;Sabine Braat

Frequent Co-Authors

Johannes G. Ramaekers
Johannes G. Ramaekers Maastricht University
Kim P. C. Kuypers
Kim P. C. Kuypers Maastricht University
Robbert-Jan Verkes
Robbert-Jan Verkes Radboud University
Claude Alain
Claude Alain University of Toronto
Mitul A. Mehta
Mitul A. Mehta King's College London
Marta Torrens
Marta Torrens Autonomous University of Barcelona
Harald Merckelbach
Harald Merckelbach Maastricht University
Margot J. Taylor
Margot J. Taylor University of Toronto
Barbara Franke
Barbara Franke Radboud University

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