Testing the dopamine overdose hypothesis in action control: A study in people with Parkinson's disease

Journal of Neuropsychology, vol. 17, pp. 264–278

Abstract

Prior work on patients with Parkinson's disease (PD) has shown that the administration of dopaminergic medication in the early to intermediate stages of PD benefits (motor) functions associated with the dopamine-depleted dorsal striatal circuitry but may 'overdose' and interfere with (cognitive) functions associated with the relatively intact ventral striatal circuitry. The present study aimed to elucidate this so-called dopamine overdose hypothesis for the action control domain. Using a within-subject design in a sample of 13 people with PD, we evaluated the effect of dopaminergic medication on two cognitive processes underlying goal-directed behaviour, namely action selection and initiation through event binding and conflict adaptation. We also investigated whether individual differences in the magnitude of medication effects were associated across these processes. Results showed no indications that dopaminergic medication affects action selection and initiation or conflict adaptation in PD patients. Additionally, we observed no correlations between both cognitive processes nor between individual differences in medication effects. Our findings do not support the notion that dopaminergic medication modulates action control processes, suggesting that the dopamine overdose hypothesis may only apply to a specific set of cognitive processes and should potentially be refined.

Authors 4

1. Marit F. L. Ruitenberg corresponding Aachen Department of Health Leiden Institute for Brain and Cognition Leiden The Netherlands Department of Health, Medical, and Neuropsychology Leiden Institute for Brain and Cognition

   Leiden University · Ghent University

   Affiliation as printed

   Department of Experimental Psychology Ghent University Ghent Belgium

   Department of Health, Medical and Neuropsychology Leiden University Leiden The Netherlands

   Leiden Institute for Brain and Cognition Leiden The Netherlands

   Department of Experimental Psychology, Ghent University, Ghent, Belgium

   Department of Health, Medical and Neuropsychology, Leiden University, Leiden, The Netherlands

   Leiden Institute for Brain and Cognition, Leiden, The Netherlands

2. Elger L. Abrahamse

   Tilburg University · Universidad del Atlántico Medio

   Affiliation as printed

   Department of Communication and Cognition Tilburg University Tilburg The Netherlands

   Department of Educational Sciences Atlántico Medio University Las Palmas Spain

   Department of Communication and Cognition, Tilburg University, Tilburg, The Netherlands

3. Patrick Santens

   Ghent University Hospital

   Affiliation as printed

   Department of Neurology Ghent University Hospital Ghent Belgium

   Department of Neurology, Ghent University Hospital, Ghent, Belgium

4. Wim Notebaert

   Ghent University

   Affiliation as printed

   Department of Experimental Psychology Ghent University Ghent Belgium

   Department of Experimental Psychology, Ghent University, Ghent, Belgium