title: Valenced action/inhibition learning in humans is modulated by a genetic variant linked to dopamine D2 receptor expression.
abstract: Motivational salience plays an important role in shaping human behavior, but recent studies demonstrate that human performance is not uniformly improved by motivation. Instead, action has been shown to dominate valence in motivated tasks, and it is particularly difficult for humans to learn the inhibition of an action to obtain a reward, but the neural mechanism behind this behavioral specificity is yet unclear. In all mammals, including humans, the monoamine neurotransmitter dopamine is particularly important in the neural manifestation of appetitively motivated behavior, and the human dopamine system is subject to considerable genetic variability. The well-studied TaqIA restriction fragment length polymorphism (rs1800497) has previously been shown to affect striatal dopamine metabolism. In this study we investigated a potential effect of this genetic variation on motivated action/inhibition learning. Two independent cohorts consisting of 87 and 95 healthy participants, respectively, were tested using the previously described valenced go/no-go learning paradigm in which participants learned the reward-associated no-go condition significantly worse than all other conditions. This effect was modulated by the TaqIA polymorphism, with carriers of the A1 allele showing a diminished learning-related performance enhancement in the rewarded no-go condition compared to the A2 homozygotes. This result highlights a modulatory role for genetic variability of the dopaminergic system in individual learning differences of action-valence interaction.
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Anni
authors.initials: A
authors.lastname: Richter
authors.affiliation: Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London London, UK ; Ageing Research Centre, Karolinska Institute Stockholm, Sweden.
authors.forename: Marc
authors.initials: M
authors.lastname: Guitart-Masip
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Adriana
authors.initials: A
authors.lastname: Barman
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Catherine
authors.initials: C
authors.lastname: Libeau
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Gusalija
authors.initials: G
authors.lastname: Behnisch
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Sophia
authors.initials: S
authors.lastname: Czerney
authors.affiliation: Institute of Human Genetics, Otto von Guericke University of Magdeburg Magdeburg, Germany.
authors.forename: Denny
authors.initials: D
authors.lastname: Schanze
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Assmann
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany.
authors.forename: Marieke
authors.initials: M
authors.lastname: Klein
authors.affiliation: Institute of Cognitive Neurology and Dementia Research, Otto von Guericke University Magdeburg Magdeburg, Germany ; Institute of Cognitive Neuroscience, University College London London, UK ; German Center for Neurodegenerative Diseases Magdeburg, Germany ; Center for Behavioral Brain Sciences, Otto von Guericke University of Magdeburg Magdeburg, Germany.
authors.forename: Emrah
authors.initials: E
authors.lastname: Düzel
authors.affiliation: Institute of Human Genetics, Otto von Guericke University of Magdeburg Magdeburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Zenker
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany ; Center for Behavioral Brain Sciences, Otto von Guericke University of Magdeburg Magdeburg, Germany.
authors.forename: Constanze I
authors.initials: CI
authors.lastname: Seidenbecher
authors.affiliation: Department of Neurochemistry and Molecular Biology, Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany ; Center for Behavioral Brain Sciences, Otto von Guericke University of Magdeburg Magdeburg, Germany ; Department of Psychiatry, Charité University Hospital Berlin, Germany ; Department of Neurology, University of Magdeburg Magdeburg, Germany.
authors.forename: Björn H
authors.initials: BH
authors.lastname: Schott
keywords: TaqIA; action bias; dopamine D2 receptor; motivated learning; reward learning