ADHD Research Group

Scientific background

Within the framework of the CoCA project (Link auf ), we are using functional magnetic resonance imaging to investigate how the reward system operates in ADHD. In a first study we tested the influence of the neurotransmitter dopamine. Study participants received a drug before completing a task that tests the reward system and were examined a total of three times using fMRI. Among other things, we were able to show for the first time that the drug L-DOPA leads to an increase in connectivity between deep, dopaminergic nuclei (VTA and substantia nigra) and cortical areas in the insula/operculum area.

We investigate the reward system using paradigms for delay discountingt: How is the decision "Do you prefer 10 € now or 15 € in 8 weeks?” represented in the brain? Obviously,impulsive people opt for the immediate reward. How does this depend on the neurotransmitter dopamine, which play a significant role in ADHD?

During the ADHD consultation in our outpatient clinic we investigate the sensitivity and specificity of concentration tests (Qb-Test, NESPLORA Aquarium) as well as their equivalence. Although many of these tests show good sensitivity, they are unspecific in comparison between psychiatric diseases such as ADHD and depression.

Within the framework of genetic studies, we investigate the genetic material of study participants in international cooperation.  In a longitudinal study, we examine patients with ADHD who already introduced themselves during our consultation hours and who took part in a first questionnaire survey.

Our research is translational, i.e. from genetic findings, to understanding and identifying of neurobiological mechanisms contributing to the disease, to application in therapy and diagnostics.


  • Functional magnetic resonance imaging (resting state measurements, special paradigms for reward delay, etc.) in collaboration with the brain imaging center (BIC) Frankfurt
  • Pharmacological provocation using dopaminergic or other substances
  • Clinical trials (PROUD -> Link auf interne Seite )
  • Genetic studies (e.g. GWAS and PRS studies )
  • Online questionnaires on ADHD and personality traits and traits (e.g. creativity)
  • Computer-aided tests of concentration (CPT, partly with motion analysis)


Mayer JS, Hees K, Medda J, et al (2018) Bright light therapy versus physical exercise to prevent co-morbid depression and obesity in adolescents and young adults with attention-deficit / hyperactivity disorder: Study protocol for a randomized controlled trial. Trials.      Eine Beschreibung der CoCA-PROUD-Studie

Grimm O, Kittel-Schneider S, Reif A (2018) Recent developments in the genetics of attention-deficit hyperactivity disorder. Psychiatry Clin Neurosci 72:654–672. Überblick über Genetik der ADHS

Grimm O, Löffler M, Kamping S, et al (2018) Probing the endocannabinoid system in healthy volunteers: Cannabidiol alters fronto-striatal resting-state connectivity. Eur Neuropsychopharmacol. Eine Pharmaco-fMRT-Studie über den Einfluss von Cannabinoiden auf das Striatum

Grimm O, Heinz A, Walter H, et al (2014) Striatal response to reward anticipation: evidence for a systems-level intermediate phenotype for schizophrenia. JAMA psychiatry 71:531–9. Eine Untersuchung des Belohnungssystems bei einer genetischen Risikogruppe


IMpACT ( )


RTOC ( )



Senior attending psychiatrist Dr. Oliver Grimm

ADHD-outpatient clinic

Nathalie Brunkhorst-Kanaan (PROUD)

Moritz Verdenhalven



Senior attending psychiatristDr. Oliver Grimm

ADHD-outpatient clinic

Nathalie Brunkhorst-Kanaan (PROUD-Study)

Moritz Verdenhalven



BSc Christian Buschenlange Vera Kopfer Kaja Kuranel Magdalena Kuhn Lea Küpper-Tetzel Vera Deppert


MSc Mirjam Back

BSc Maren Ballhausen

Inquiries regarding internships, theses and dissertations

Within the framework of the projects mentioned above, internships or theses in psychology, medicine, neurosciences and related subjects are possible (BSc, MSc, Dr. med.). When working with patients, a solid knowledge of German is essential (at least B2Basic knowledge in statistics and computer skills are useful when analyzing and maintaining data sets. If you are interested in working with us, please send a short letter of motivation and a curriculum vitae in tabular form to

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