Evidence for absence of links between striatal dopamine synthesis capacity and working memory capacity, spontaneous eye-blink rate, and trait impulsivity
- Radboud University Nijmegen, Netherlands
- Stockholm University, Sweden
- University of Amsterdam, Netherlands
- Radboud University Nijmegen Medical Centre, Netherlands
- Amsterdam University Medical Centers, Netherlands
Abstract
Individual differences in striatal dopamine synthesis capacity have been associated with working memory capacity, trait impulsivity and spontaneous eye-blink rate (sEBR), as measured with readily available and easily administered, 'off-the-shelf' tests. Such findings have raised the suggestion that individual variation in dopamine synthesis capacity, estimated with expensive and invasive brain positron emission tomography (PET) scans, can be approximated with simple, more pragmatic tests. However, direct evidence for the relationship between these simple trait measures and striatal dopamine synthesis capacity has been limited and inconclusive. We measured striatal dopamine synthesis capacity using [18F]-FDOPA PET in a large sample of healthy volunteers (N=94) and assessed the correlation with simple, short tests of working memory capacity, trait impulsivity, and sEBR. We additionally explored the relationship with an index of subjective reward sensitivity. None of these trait measures correlated significantly with striatal dopamine synthesis capacity, nor did they have out-of-sample predictive power. Bayes Factor analyses indicated the evidence was in favour of absence of correlations for all but subjective reward sensitivity. These results warrant caution for using these off-the-shelf trait measures as proxies of striatal dopamine synthesis capacity.
Data availability
The minimally processed data used in this study and the overarching project it is part of are available from the Donders Institute Data Repository (https://doi.org/10.34973/wn51-ej53; custom data use agreement RU-DI-HD-1.0). The final data derivatives relevant to the current work, as well as all code for data analysis and figures creation, are available from a separate collection on the Donders Institute Data Repository (https://doi.org/10.34973/0sce-z290).
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Effects of sulpiride and methylphenidate on brain and cognition: a PET pharmaco-fMRI studyDonders Institute Data Repository (di.dccn.DSC_3017048.01_875).
Article and author information
Author details
Ruben van den Bosch
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (453-14-015)
- Roshan Cools
Horizon 2020 Framework Programme (945539)
- Roshan Cools
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants provided written informed consent. The study was approved by the local ethics committee ("Commissie Mensgebonden Onderzoek", CMO region Arnhem-Nijmegen, The Netherlands: protocol NL57538.091.16).
Copyright
© 2023, van den Bosch et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Evidence for absence of links between striatal dopamine synthesis capacity and working memory capacity, spontaneous eye-blink rate, and trait impulsivity
eLife 12:e83161.
https://doi.org/10.7554/eLife.83161
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